summaryrefslogtreecommitdiffstats
path: root/drivers/usb/core/devio.c
blob: 32e5591ae7b17edce9cd4e142879d99b58422683 (plain)
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
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
/*****************************************************************************/

/*
 *      devio.c  --  User space communication with USB devices.
 *
 *      Copyright (C) 1999-2000  Thomas Sailer (sailer@ife.ee.ethz.ch)
 *
 *      This program is free software; you can redistribute it and/or modify
 *      it under the terms of the GNU General Public License as published by
 *      the Free Software Foundation; either version 2 of the License, or
 *      (at your option) any later version.
 *
 *      This program is distributed in the hope that it will be useful,
 *      but WITHOUT ANY WARRANTY; without even the implied warranty of
 *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *      GNU General Public License for more details.
 *
 *      You should have received a copy of the GNU General Public License
 *      along with this program; if not, write to the Free Software
 *      Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *  $Id: devio.c,v 1.7 2000/02/01 17:28:48 fliegl Exp $
 *
 *  This file implements the usbfs/x/y files, where
 *  x is the bus number and y the device number.
 *
 *  It allows user space programs/"drivers" to communicate directly
 *  with USB devices without intervening kernel driver.
 *
 *  Revision history
 *    22.12.1999   0.1   Initial release (split from proc_usb.c)
 *    04.01.2000   0.2   Turned into its own filesystem
 *    30.09.2005   0.3   Fix user-triggerable oops in async URB delivery
 *    			 (CAN-2005-3055)
 */

/*****************************************************************************/

#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/smp_lock.h>
#include <linux/signal.h>
#include <linux/poll.h>
#include <linux/module.h>
#include <linux/usb.h>
#include <linux/usbdevice_fs.h>
#include <linux/cdev.h>
#include <linux/notifier.h>
#include <linux/security.h>
#include <asm/uaccess.h>
#include <asm/byteorder.h>
#include <linux/moduleparam.h>

#include "hcd.h"	/* for usbcore internals */
#include "usb.h"

#define USB_MAXBUS			64
#define USB_DEVICE_MAX			USB_MAXBUS * 128

/* Mutual exclusion for removal, open, and release */
DEFINE_MUTEX(usbfs_mutex);

struct async {
	struct list_head asynclist;
	struct dev_state *ps;
	struct pid *pid;
	uid_t uid, euid;
	unsigned int signr;
	unsigned int ifnum;
	void __user *userbuffer;
	void __user *userurb;
	struct urb *urb;
	int status;
	u32 secid;
};

static int usbfs_snoop = 0;
module_param (usbfs_snoop, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC (usbfs_snoop, "true to log all usbfs traffic");

#define snoop(dev, format, arg...)				\
	do {							\
		if (usbfs_snoop)				\
			dev_info( dev , format , ## arg);	\
	} while (0)

#define USB_DEVICE_DEV		MKDEV(USB_DEVICE_MAJOR, 0)


#define	MAX_USBFS_BUFFER_SIZE	16384

static inline int connected (struct dev_state *ps)
{
	return (!list_empty(&ps->list) &&
			ps->dev->state != USB_STATE_NOTATTACHED);
}

static loff_t usbdev_lseek(struct file *file, loff_t offset, int orig)
{
	loff_t ret;

	lock_kernel();

	switch (orig) {
	case 0:
		file->f_pos = offset;
		ret = file->f_pos;
		break;
	case 1:
		file->f_pos += offset;
		ret = file->f_pos;
		break;
	case 2:
	default:
		ret = -EINVAL;
	}

	unlock_kernel();
	return ret;
}

static ssize_t usbdev_read(struct file *file, char __user *buf, size_t nbytes, loff_t *ppos)
{
	struct dev_state *ps = file->private_data;
	struct usb_device *dev = ps->dev;
	ssize_t ret = 0;
	unsigned len;
	loff_t pos;
	int i;

	pos = *ppos;
	usb_lock_device(dev);
	if (!connected(ps)) {
		ret = -ENODEV;
		goto err;
	} else if (pos < 0) {
		ret = -EINVAL;
		goto err;
	}

	if (pos < sizeof(struct usb_device_descriptor)) {
		struct usb_device_descriptor temp_desc ; /* 18 bytes - fits on the stack */

		memcpy(&temp_desc, &dev->descriptor, sizeof(dev->descriptor));
		le16_to_cpus(&temp_desc.bcdUSB);
		le16_to_cpus(&temp_desc.idVendor);
		le16_to_cpus(&temp_desc.idProduct);
		le16_to_cpus(&temp_desc.bcdDevice);

		len = sizeof(struct usb_device_descriptor) - pos;
		if (len > nbytes)
			len = nbytes;
		if (copy_to_user(buf, ((char *)&temp_desc) + pos, len)) {
			ret = -EFAULT;
			goto err;
		}

		*ppos += len;
		buf += len;
		nbytes -= len;
		ret += len;
	}

	pos = sizeof(struct usb_device_descriptor);
	for (i = 0; nbytes && i < dev->descriptor.bNumConfigurations; i++) {
		struct usb_config_descriptor *config =
			(struct usb_config_descriptor *)dev->rawdescriptors[i];
		unsigned int length = le16_to_cpu(config->wTotalLength);

		if (*ppos < pos + length) {

			/* The descriptor may claim to be longer than it
			 * really is.  Here is the actual allocated length. */
			unsigned alloclen =
				le16_to_cpu(dev->config[i].desc.wTotalLength);

			len = length - (*ppos - pos);
			if (len > nbytes)
				len = nbytes;

			/* Simply don't write (skip over) unallocated parts */
			if (alloclen > (*ppos - pos)) {
				alloclen -= (*ppos - pos);
				if (copy_to_user(buf,
				    dev->rawdescriptors[i] + (*ppos - pos),
				    min(len, alloclen))) {
					ret = -EFAULT;
					goto err;
				}
			}

			*ppos += len;
			buf += len;
			nbytes -= len;
			ret += len;
		}

		pos += length;
	}

err:
	usb_unlock_device(dev);
	return ret;
}

/*
 * async list handling
 */

static struct async *alloc_async(unsigned int numisoframes)
{
        unsigned int assize = sizeof(struct async) + numisoframes * sizeof(struct usb_iso_packet_descriptor);
        struct async *as = kzalloc(assize, GFP_KERNEL);

        if (!as)
                return NULL;
	as->urb = usb_alloc_urb(numisoframes, GFP_KERNEL);
	if (!as->urb) {
		kfree(as);
		return NULL;
	}
        return as;
}

static void free_async(struct async *as)
{
	put_pid(as->pid);
	kfree(as->urb->transfer_buffer);
	kfree(as->urb->setup_packet);
	usb_free_urb(as->urb);
	kfree(as);
}

static inline void async_newpending(struct async *as)
{
        struct dev_state *ps = as->ps;
        unsigned long flags;
        
        spin_lock_irqsave(&ps->lock, flags);
        list_add_tail(&as->asynclist, &ps->async_pending);
        spin_unlock_irqrestore(&ps->lock, flags);
}

static inline void async_removepending(struct async *as)
{
        struct dev_state *ps = as->ps;
        unsigned long flags;
        
        spin_lock_irqsave(&ps->lock, flags);
        list_del_init(&as->asynclist);
        spin_unlock_irqrestore(&ps->lock, flags);
}

static inline struct async *async_getcompleted(struct dev_state *ps)
{
        unsigned long flags;
        struct async *as = NULL;

        spin_lock_irqsave(&ps->lock, flags);
        if (!list_empty(&ps->async_completed)) {
                as = list_entry(ps->async_completed.next, struct async, asynclist);
                list_del_init(&as->asynclist);
        }
        spin_unlock_irqrestore(&ps->lock, flags);
        return as;
}

static inline struct async *async_getpending(struct dev_state *ps, void __user *userurb)
{
        unsigned long flags;
        struct async *as;

        spin_lock_irqsave(&ps->lock, flags);
	list_for_each_entry(as, &ps->async_pending, asynclist)
		if (as->userurb == userurb) {
			list_del_init(&as->asynclist);
			spin_unlock_irqrestore(&ps->lock, flags);
			return as;
		}
        spin_unlock_irqrestore(&ps->lock, flags);
        return NULL;
}

static void snoop_urb(struct urb *urb, void __user *userurb)
{
	int j;
	unsigned char *data = urb->transfer_buffer;

	if (!usbfs_snoop)
		return;

	dev_info(&urb->dev->dev, "direction=%s\n",
			usb_urb_dir_in(urb) ? "IN" : "OUT");
	dev_info(&urb->dev->dev, "userurb=%p\n", userurb);
	dev_info(&urb->dev->dev, "transfer_buffer_length=%d\n",
		 urb->transfer_buffer_length);
	dev_info(&urb->dev->dev, "actual_length=%d\n", urb->actual_length);
	dev_info(&urb->dev->dev, "data: ");
	for (j = 0; j < urb->transfer_buffer_length; ++j)
		printk ("%02x ", data[j]);
	printk("\n");
}

static void async_completed(struct urb *urb)
{
        struct async *as = urb->context;
        struct dev_state *ps = as->ps;
	struct siginfo sinfo;

        spin_lock(&ps->lock);
        list_move_tail(&as->asynclist, &ps->async_completed);
        spin_unlock(&ps->lock);
	as->status = urb->status;
	if (as->signr) {
		sinfo.si_signo = as->signr;
		sinfo.si_errno = as->status;
		sinfo.si_code = SI_ASYNCIO;
		sinfo.si_addr = as->userurb;
		kill_pid_info_as_uid(as->signr, &sinfo, as->pid, as->uid,
				      as->euid, as->secid);
	}
	snoop(&urb->dev->dev, "urb complete\n");
	snoop_urb(urb, as->userurb);
	wake_up(&ps->wait);
}

static void destroy_async (struct dev_state *ps, struct list_head *list)
{
	struct async *as;
	unsigned long flags;

	spin_lock_irqsave(&ps->lock, flags);
	while (!list_empty(list)) {
		as = list_entry(list->next, struct async, asynclist);
		list_del_init(&as->asynclist);

		/* drop the spinlock so the completion handler can run */
		spin_unlock_irqrestore(&ps->lock, flags);
		usb_kill_urb(as->urb);
		spin_lock_irqsave(&ps->lock, flags);
	}
	spin_unlock_irqrestore(&ps->lock, flags);
	as = async_getcompleted(ps);
	while (as) {
		free_async(as);
		as = async_getcompleted(ps);
	}
}

static void destroy_async_on_interface (struct dev_state *ps, unsigned int ifnum)
{
	struct list_head *p, *q, hitlist;
	unsigned long flags;

	INIT_LIST_HEAD(&hitlist);
	spin_lock_irqsave(&ps->lock, flags);
	list_for_each_safe(p, q, &ps->async_pending)
		if (ifnum == list_entry(p, struct async, asynclist)->ifnum)
			list_move_tail(p, &hitlist);
	spin_unlock_irqrestore(&ps->lock, flags);
	destroy_async(ps, &hitlist);
}

static inline void destroy_all_async(struct dev_state *ps)
{
	        destroy_async(ps, &ps->async_pending);
}

/*
 * interface claims are made only at the request of user level code,
 * which can also release them (explicitly or by closing files).
 * they're also undone when devices disconnect.
 */

static int driver_probe (struct usb_interface *intf,
			 const struct usb_device_id *id)
{
	return -ENODEV;
}

static void driver_disconnect(struct usb_interface *intf)
{
	struct dev_state *ps = usb_get_intfdata (intf);
	unsigned int ifnum = intf->altsetting->desc.bInterfaceNumber;

	if (!ps)
		return;

	/* NOTE:  this relies on usbcore having canceled and completed
	 * all pending I/O requests; 2.6 does that.
	 */

	if (likely(ifnum < 8*sizeof(ps->ifclaimed)))
		clear_bit(ifnum, &ps->ifclaimed);
	else
		warn("interface number %u out of range", ifnum);

	usb_set_intfdata (intf, NULL);

	/* force async requests to complete */
	destroy_async_on_interface(ps, ifnum);
}

/* The following routines are merely placeholders.  There is no way
 * to inform a user task about suspend or resumes.
 */
static int driver_suspend(struct usb_interface *intf, pm_message_t msg)
{
	return 0;
}

static int driver_resume(struct usb_interface *intf)
{
	return 0;
}

struct usb_driver usbfs_driver = {
	.name =		"usbfs",
	.probe =	driver_probe,
	.disconnect =	driver_disconnect,
	.suspend =	driver_suspend,
	.resume =	driver_resume,
};

static int claimintf(struct dev_state *ps, unsigned int ifnum)
{
	struct usb_device *dev = ps->dev;
	struct usb_interface *intf;
	int err;

	if (ifnum >= 8*sizeof(ps->ifclaimed))
		return -EINVAL;
	/* already claimed */
	if (test_bit(ifnum, &ps->ifclaimed))
		return 0;

	intf = usb_ifnum_to_if(dev, ifnum);
	if (!intf)
		err = -ENOENT;
	else
		err = usb_driver_claim_interface(&usbfs_driver, intf, ps);
	if (err == 0)
		set_bit(ifnum, &ps->ifclaimed);
	return err;
}

static int releaseintf(struct dev_state *ps, unsigned int ifnum)
{
	struct usb_device *dev;
	struct usb_interface *intf;
	int err;

	err = -EINVAL;
	if (ifnum >= 8*sizeof(ps->ifclaimed))
		return err;
	dev = ps->dev;
	intf = usb_ifnum_to_if(dev, ifnum);
	if (!intf)
		err = -ENOENT;
	else if (test_and_clear_bit(ifnum, &ps->ifclaimed)) {
		usb_driver_release_interface(&usbfs_driver, intf);
		err = 0;
	}
	return err;
}

static int checkintf(struct dev_state *ps, unsigned int ifnum)
{
	if (ps->dev->state != USB_STATE_CONFIGURED)
		return -EHOSTUNREACH;
	if (ifnum >= 8*sizeof(ps->ifclaimed))
		return -EINVAL;
	if (test_bit(ifnum, &ps->ifclaimed))
		return 0;
	/* if not yet claimed, claim it for the driver */
	dev_warn(&ps->dev->dev, "usbfs: process %d (%s) did not claim interface %u before use\n",
	       task_pid_nr(current), current->comm, ifnum);
	return claimintf(ps, ifnum);
}

static int findintfep(struct usb_device *dev, unsigned int ep)
{
	unsigned int i, j, e;
        struct usb_interface *intf;
	struct usb_host_interface *alts;
	struct usb_endpoint_descriptor *endpt;

	if (ep & ~(USB_DIR_IN|0xf))
		return -EINVAL;
	if (!dev->actconfig)
		return -ESRCH;
	for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++) {
		intf = dev->actconfig->interface[i];
		for (j = 0; j < intf->num_altsetting; j++) {
                        alts = &intf->altsetting[j];
			for (e = 0; e < alts->desc.bNumEndpoints; e++) {
				endpt = &alts->endpoint[e].desc;
				if (endpt->bEndpointAddress == ep)
					return alts->desc.bInterfaceNumber;
			}
		}
	}
	return -ENOENT; 
}

static int check_ctrlrecip(struct dev_state *ps, unsigned int requesttype, unsigned int index)
{
	int ret = 0;

	if (ps->dev->state != USB_STATE_ADDRESS
	 && ps->dev->state != USB_STATE_CONFIGURED)
		return -EHOSTUNREACH;
	if (USB_TYPE_VENDOR == (USB_TYPE_MASK & requesttype))
		return 0;

	index &= 0xff;
	switch (requesttype & USB_RECIP_MASK) {
	case USB_RECIP_ENDPOINT:
		if ((ret = findintfep(ps->dev, index)) >= 0)
			ret = checkintf(ps, ret);
		break;

	case USB_RECIP_INTERFACE:
		ret = checkintf(ps, index);
		break;
	}
	return ret;
}

static int __match_minor(struct device *dev, void *data)
{
	int minor = *((int *)data);

	if (dev->devt == MKDEV(USB_DEVICE_MAJOR, minor))
		return 1;
	return 0;
}

static struct usb_device *usbdev_lookup_by_minor(int minor)
{
	struct device *dev;

	dev = bus_find_device(&usb_bus_type, NULL, &minor, __match_minor);
	if (!dev)
		return NULL;
	put_device(dev);
	return container_of(dev, struct usb_device, dev);
}

/*
 * file operations
 */
static int usbdev_open(struct inode *inode, struct file *file)
{
	struct usb_device *dev = NULL;
	struct dev_state *ps;
	int ret;

	/* Protect against simultaneous removal or release */
	mutex_lock(&usbfs_mutex);

	ret = -ENOMEM;
	if (!(ps = kmalloc(sizeof(struct dev_state), GFP_KERNEL)))
		goto out;

	ret = -ENOENT;
	/* usbdev device-node */
	if (imajor(inode) == USB_DEVICE_MAJOR)
		dev = usbdev_lookup_by_minor(iminor(inode));
#ifdef CONFIG_USB_DEVICEFS
	/* procfs file */
	if (!dev)
		dev = inode->i_private;
#endif
	if (!dev)
		goto out;
	ret = usb_autoresume_device(dev);
	if (ret)
		goto out;

	usb_get_dev(dev);
	ret = 0;
	ps->dev = dev;
	ps->file = file;
	spin_lock_init(&ps->lock);
	INIT_LIST_HEAD(&ps->list);
	INIT_LIST_HEAD(&ps->async_pending);
	INIT_LIST_HEAD(&ps->async_completed);
	init_waitqueue_head(&ps->wait);
	ps->discsignr = 0;
	ps->disc_pid = get_pid(task_pid(current));
	ps->disc_uid = current->uid;
	ps->disc_euid = current->euid;
	ps->disccontext = NULL;
	ps->ifclaimed = 0;
	security_task_getsecid(current, &ps->secid);
	smp_wmb();
	list_add_tail(&ps->list, &dev->filelist);
	file->private_data = ps;
 out:
	if (ret)
		kfree(ps);
	mutex_unlock(&usbfs_mutex);
	return ret;
}

static int usbdev_release(struct inode *inode, struct file *file)
{
	struct dev_state *ps = file->private_data;
	struct usb_device *dev = ps->dev;
	unsigned int ifnum;

	usb_lock_device(dev);

	/* Protect against simultaneous open */
	mutex_lock(&usbfs_mutex);
	list_del_init(&ps->list);
	mutex_unlock(&usbfs_mutex);

	for (ifnum = 0; ps->ifclaimed && ifnum < 8*sizeof(ps->ifclaimed);
			ifnum++) {
		if (test_bit(ifnum, &ps->ifclaimed))
			releaseintf(ps, ifnum);
	}
	destroy_all_async(ps);
	usb_autosuspend_device(dev);
	usb_unlock_device(dev);
	usb_put_dev(dev);
	put_pid(ps->disc_pid);
	kfree(ps);
	return 0;
}

static int proc_control(struct dev_state *ps, void __user *arg)
{
	struct usb_device *dev = ps->dev;
	struct usbdevfs_ctrltransfer ctrl;
	unsigned int tmo;
	unsigned char *tbuf;
	int i, j, ret;

	if (copy_from_user(&ctrl, arg, sizeof(ctrl)))
		return -EFAULT;
	if ((ret = check_ctrlrecip(ps, ctrl.bRequestType, ctrl.wIndex)))
		return ret;
	if (ctrl.wLength > PAGE_SIZE)
		return -EINVAL;
	if (!(tbuf = (unsigned char *)__get_free_page(GFP_KERNEL)))
		return -ENOMEM;
	tmo = ctrl.timeout;
	if (ctrl.bRequestType & 0x80) {
		if (ctrl.wLength && !access_ok(VERIFY_WRITE, ctrl.data, ctrl.wLength)) {
			free_page((unsigned long)tbuf);
			return -EINVAL;
		}
		snoop(&dev->dev, "control read: bRequest=%02x "
				"bRrequestType=%02x wValue=%04x "
				"wIndex=%04x wLength=%04x\n",
			ctrl.bRequest, ctrl.bRequestType, ctrl.wValue,
				ctrl.wIndex, ctrl.wLength);

		usb_unlock_device(dev);
		i = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), ctrl.bRequest, ctrl.bRequestType,
				       ctrl.wValue, ctrl.wIndex, tbuf, ctrl.wLength, tmo);
		usb_lock_device(dev);
		if ((i > 0) && ctrl.wLength) {
			if (usbfs_snoop) {
				dev_info(&dev->dev, "control read: data ");
				for (j = 0; j < i; ++j)
					printk("%02x ", (unsigned char)(tbuf)[j]);
				printk("\n");
			}
			if (copy_to_user(ctrl.data, tbuf, i)) {
				free_page((unsigned long)tbuf);
				return -EFAULT;
			}
		}
	} else {
		if (ctrl.wLength) {
			if (copy_from_user(tbuf, ctrl.data, ctrl.wLength)) {
				free_page((unsigned long)tbuf);
				return -EFAULT;
			}
		}
		snoop(&dev->dev, "control write: bRequest=%02x "
				"bRrequestType=%02x wValue=%04x "
				"wIndex=%04x wLength=%04x\n",
			ctrl.bRequest, ctrl.bRequestType, ctrl.wValue,
				ctrl.wIndex, ctrl.wLength);
		if (usbfs_snoop) {
			dev_info(&dev->dev, "control write: data: ");
			for (j = 0; j < ctrl.wLength; ++j)
				printk("%02x ", (unsigned char)(tbuf)[j]);
			printk("\n");
		}
		usb_unlock_device(dev);
		i = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), ctrl.bRequest, ctrl.bRequestType,
				       ctrl.wValue, ctrl.wIndex, tbuf, ctrl.wLength, tmo);
		usb_lock_device(dev);
	}
	free_page((unsigned long)tbuf);
	if (i<0 && i != -EPIPE) {
		dev_printk(KERN_DEBUG, &dev->dev, "usbfs: USBDEVFS_CONTROL "
			   "failed cmd %s rqt %u rq %u len %u ret %d\n",
			   current->comm, ctrl.bRequestType, ctrl.bRequest,
			   ctrl.wLength, i);
	}
	return i;
}

static int proc_bulk(struct dev_state *ps, void __user *arg)
{
	struct usb_device *dev = ps->dev;
	struct usbdevfs_bulktransfer bulk;
	unsigned int tmo, len1, pipe;
	int len2;
	unsigned char *tbuf;
	int i, j, ret;

	if (copy_from_user(&bulk, arg, sizeof(bulk)))
		return -EFAULT;
	if ((ret = findintfep(ps->dev, bulk.ep)) < 0)
		return ret;
	if ((ret = checkintf(ps, ret)))
		return ret;
	if (bulk.ep & USB_DIR_IN)
		pipe = usb_rcvbulkpipe(dev, bulk.ep & 0x7f);
	else
		pipe = usb_sndbulkpipe(dev, bulk.ep & 0x7f);
	if (!usb_maxpacket(dev, pipe, !(bulk.ep & USB_DIR_IN)))
		return -EINVAL;
	len1 = bulk.len;
	if (len1 > MAX_USBFS_BUFFER_SIZE)
		return -EINVAL;
	if (!(tbuf = kmalloc(len1, GFP_KERNEL)))
		return -ENOMEM;
	tmo = bulk.timeout;
	if (bulk.ep & 0x80) {
		if (len1 && !access_ok(VERIFY_WRITE, bulk.data, len1)) {
			kfree(tbuf);
			return -EINVAL;
		}
		snoop(&dev->dev, "bulk read: len=0x%02x timeout=%04d\n",
			bulk.len, bulk.timeout);
		usb_unlock_device(dev);
		i = usb_bulk_msg(dev, pipe, tbuf, len1, &len2, tmo);
		usb_lock_device(dev);
		if (!i && len2) {
			if (usbfs_snoop) {
				dev_info(&dev->dev, "bulk read: data ");
				for (j = 0; j < len2; ++j)
					printk("%02x ", (unsigned char)(tbuf)[j]);
				printk("\n");
			}
			if (copy_to_user(bulk.data, tbuf, len2)) {
				kfree(tbuf);
				return -EFAULT;
			}
		}
	} else {
		if (len1) {
			if (copy_from_user(tbuf, bulk.data, len1)) {
				kfree(tbuf);
				return -EFAULT;
			}
		}
		snoop(&dev->dev, "bulk write: len=0x%02x timeout=%04d\n",
			bulk.len, bulk.timeout);
		if (usbfs_snoop) {
			dev_info(&dev->dev, "bulk write: data: ");
			for (j = 0; j < len1; ++j)
				printk("%02x ", (unsigned char)(tbuf)[j]);
			printk("\n");
		}
		usb_unlock_device(dev);
		i = usb_bulk_msg(dev, pipe, tbuf, len1, &len2, tmo);
		usb_lock_device(dev);
	}
	kfree(tbuf);
	if (i < 0)
		return i;
	return len2;
}

static int proc_resetep(struct dev_state *ps, void __user *arg)
{
	unsigned int ep;
	int ret;

	if (get_user(ep, (unsigned int __user *)arg))
		return -EFAULT;
	if ((ret = findintfep(ps->dev, ep)) < 0)
		return ret;
	if ((ret = checkintf(ps, ret)))
		return ret;
	usb_settoggle(ps->dev, ep & 0xf, !(ep & USB_DIR_IN), 0);
	return 0;
}

static int proc_clearhalt(struct dev_state *ps, void __user *arg)
{
	unsigned int ep;
	int pipe;
	int ret;

	if (get_user(ep, (unsigned int __user *)arg))
		return -EFAULT;
	if ((ret = findintfep(ps->dev, ep)) < 0)
		return ret;
	if ((ret = checkintf(ps, ret)))
		return ret;
	if (ep & USB_DIR_IN)
                pipe = usb_rcvbulkpipe(ps->dev, ep & 0x7f);
        else
                pipe = usb_sndbulkpipe(ps->dev, ep & 0x7f);

	return usb_clear_halt(ps->dev, pipe);
}
		

static int proc_getdriver(struct dev_state *ps, void __user *arg)
{
	struct usbdevfs_getdriver gd;
	struct usb_interface *intf;
	int ret;

	if (copy_from_user(&gd, arg, sizeof(gd)))
		return -EFAULT;
	intf = usb_ifnum_to_if(ps->dev, gd.interface);
	if (!intf || !intf->dev.driver)
		ret = -ENODATA;
	else {
		strncpy(gd.driver, intf->dev.driver->name,
				sizeof(gd.driver));
		ret = (copy_to_user(arg, &gd, sizeof(gd)) ? -EFAULT : 0);
	}
	return ret;
}

static int proc_connectinfo(struct dev_state *ps, void __user *arg)
{
	struct usbdevfs_connectinfo ci;

	ci.devnum = ps->dev->devnum;
	ci.slow = ps->dev->speed == USB_SPEED_LOW;
	if (copy_to_user(arg, &ci, sizeof(ci)))
		return -EFAULT;
	return 0;
}

static int proc_resetdevice(struct dev_state *ps)
{
	return usb_reset_composite_device(ps->dev, NULL);
}

static int proc_setintf(struct dev_state *ps, void __user *arg)
{
	struct usbdevfs_setinterface setintf;
	int ret;

	if (copy_from_user(&setintf, arg, sizeof(setintf)))
		return -EFAULT;
	if ((ret = checkintf(ps, setintf.interface)))
		return ret;
	return usb_set_interface(ps->dev, setintf.interface,
			setintf.altsetting);
}

static int proc_setconfig(struct dev_state *ps, void __user *arg)
{
	int u;
	int status = 0;
 	struct usb_host_config *actconfig;

	if (get_user(u, (int __user *)arg))
		return -EFAULT;

 	actconfig = ps->dev->actconfig;
 
 	/* Don't touch the device if any interfaces are claimed.
 	 * It could interfere with other drivers' operations, and if
	 * an interface is claimed by usbfs it could easily deadlock.
	 */
 	if (actconfig) {
 		int i;
 
 		for (i = 0; i < actconfig->desc.bNumInterfaces; ++i) {
 			if (usb_interface_claimed(actconfig->interface[i])) {
				dev_warn (&ps->dev->dev,
					"usbfs: interface %d claimed by %s "
					"while '%s' sets config #%d\n",
					actconfig->interface[i]
						->cur_altsetting
						->desc.bInterfaceNumber,
					actconfig->interface[i]
						->dev.driver->name,
					current->comm, u);
 				status = -EBUSY;
				break;
			}
 		}
 	}

	/* SET_CONFIGURATION is often abused as a "cheap" driver reset,
	 * so avoid usb_set_configuration()'s kick to sysfs
	 */
	if (status == 0) {
		if (actconfig && actconfig->desc.bConfigurationValue == u)
			status = usb_reset_configuration(ps->dev);
		else
			status = usb_set_configuration(ps->dev, u);
	}

	return status;
}

static int proc_do_submiturb(struct dev_state *ps, struct usbdevfs_urb *uurb,
			     struct usbdevfs_iso_packet_desc __user *iso_frame_desc,
			     void __user *arg)
{
	struct usbdevfs_iso_packet_desc *isopkt = NULL;
	struct usb_host_endpoint *ep;
	struct async *as;
	struct usb_ctrlrequest *dr = NULL;
	unsigned int u, totlen, isofrmlen;
	int ret, ifnum = -1;
	int is_in;

	if (uurb->flags & ~(USBDEVFS_URB_ISO_ASAP|USBDEVFS_URB_SHORT_NOT_OK|
			   URB_NO_FSBR|URB_ZERO_PACKET))
		return -EINVAL;
	if (!uurb->buffer)
		return -EINVAL;
	if (uurb->signr != 0 && (uurb->signr < SIGRTMIN || uurb->signr > SIGRTMAX))
		return -EINVAL;
	if (!(uurb->type == USBDEVFS_URB_TYPE_CONTROL && (uurb->endpoint & ~USB_ENDPOINT_DIR_MASK) == 0)) {
		if ((ifnum = findintfep(ps->dev, uurb->endpoint)) < 0)
			return ifnum;
		if ((ret = checkintf(ps, ifnum)))
			return ret;
	}
	if ((uurb->endpoint & USB_ENDPOINT_DIR_MASK) != 0) {
		is_in = 1;
		ep = ps->dev->ep_in[uurb->endpoint & USB_ENDPOINT_NUMBER_MASK];
	} else {
		is_in = 0;
		ep = ps->dev->ep_out[uurb->endpoint & USB_ENDPOINT_NUMBER_MASK];
	}
	if (!ep)
		return -ENOENT;
	switch(uurb->type) {
	case USBDEVFS_URB_TYPE_CONTROL:
		if (!usb_endpoint_xfer_control(&ep->desc))
			return -EINVAL;
		/* min 8 byte setup packet, max 8 byte setup plus an arbitrary data stage */
		if (uurb->buffer_length < 8 || uurb->buffer_length > (8 + MAX_USBFS_BUFFER_SIZE))
			return -EINVAL;
		if (!(dr = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL)))
			return -ENOMEM;
		if (copy_from_user(dr, uurb->buffer, 8)) {
			kfree(dr);
			return -EFAULT;
		}
		if (uurb->buffer_length < (le16_to_cpup(&dr->wLength) + 8)) {
			kfree(dr);
			return -EINVAL;
		}
		if ((ret = check_ctrlrecip(ps, dr->bRequestType, le16_to_cpup(&dr->wIndex)))) {
			kfree(dr);
			return ret;
		}
		uurb->number_of_packets = 0;
		uurb->buffer_length = le16_to_cpup(&dr->wLength);
		uurb->buffer += 8;
		if ((dr->bRequestType & USB_DIR_IN) && uurb->buffer_length) {
			is_in = 1;
			uurb->endpoint |= USB_DIR_IN;
		} else {
			is_in = 0;
			uurb->endpoint &= ~USB_DIR_IN;
		}
		if (!access_ok(is_in ? VERIFY_WRITE : VERIFY_READ,
				uurb->buffer, uurb->buffer_length)) {
			kfree(dr);
			return -EFAULT;
		}
		snoop(&ps->dev->dev, "control urb: bRequest=%02x "
			"bRrequestType=%02x wValue=%04x "
			"wIndex=%04x wLength=%04x\n",
			dr->bRequest, dr->bRequestType,
			__le16_to_cpup(&dr->wValue),
			__le16_to_cpup(&dr->wIndex),
			__le16_to_cpup(&dr->wLength));
		break;

	case USBDEVFS_URB_TYPE_BULK:
		switch (usb_endpoint_type(&ep->desc)) {
		case USB_ENDPOINT_XFER_CONTROL:
		case USB_ENDPOINT_XFER_ISOC:
			return -EINVAL;
		/* allow single-shot interrupt transfers, at bogus rates */
		}
		uurb->number_of_packets = 0;
		if (uurb->buffer_length > MAX_USBFS_BUFFER_SIZE)
			return -EINVAL;
		if (!access_ok(is_in ? VERIFY_WRITE : VERIFY_READ,
				uurb->buffer, uurb->buffer_length))
			return -EFAULT;
		snoop(&ps->dev->dev, "bulk urb\n");
		break;

	case USBDEVFS_URB_TYPE_ISO:
		/* arbitrary limit */
		if (uurb->number_of_packets < 1 || uurb->number_of_packets > 128)
			return -EINVAL;
		if (!usb_endpoint_xfer_isoc(&ep->desc))
			return -EINVAL;
		isofrmlen = sizeof(struct usbdevfs_iso_packet_desc) * uurb->number_of_packets;
		if (!(isopkt = kmalloc(isofrmlen, GFP_KERNEL)))
			return -ENOMEM;
		if (copy_from_user(isopkt, iso_frame_desc, isofrmlen)) {
			kfree(isopkt);
			return -EFAULT;
		}
		for (totlen = u = 0; u < uurb->number_of_packets; u++) {
			/* arbitrary limit, sufficient for USB 2.0 high-bandwidth iso */
			if (isopkt[u].length > 8192) {
				kfree(isopkt);
				return -EINVAL;
			}
			totlen += isopkt[u].length;
		}
		if (totlen > 32768) {
			kfree(isopkt);
			return -EINVAL;
		}
		uurb->buffer_length = totlen;
		snoop(&ps->dev->dev, "iso urb\n");
		break;

	case USBDEVFS_URB_TYPE_INTERRUPT:
		uurb->number_of_packets = 0;
		if (!usb_endpoint_xfer_int(&ep->desc))
			return -EINVAL;
		if (uurb->buffer_length > MAX_USBFS_BUFFER_SIZE)
			return -EINVAL;
		if (!access_ok(is_in ? VERIFY_WRITE : VERIFY_READ,
				uurb->buffer, uurb->buffer_length))
			return -EFAULT;
		snoop(&ps->dev->dev, "interrupt urb\n");
		break;

	default:
		return -EINVAL;
	}
	if (!(as = alloc_async(uurb->number_of_packets))) {
		kfree(isopkt);
		kfree(dr);
		return -ENOMEM;
	}
	if (!(as->urb->transfer_buffer = kmalloc(uurb->buffer_length, GFP_KERNEL))) {
		kfree(isopkt);
		kfree(dr);
		free_async(as);
		return -ENOMEM;
	}
        as->urb->dev = ps->dev;
        as->urb->pipe = (uurb->type << 30) |
			__create_pipe(ps->dev, uurb->endpoint & 0xf) |
			(uurb->endpoint & USB_DIR_IN);
        as->urb->transfer_flags = uurb->flags |
			(is_in ? URB_DIR_IN : URB_DIR_OUT);
	as->urb->transfer_buffer_length = uurb->buffer_length;
	as->urb->setup_packet = (unsigned char*)dr;
	as->urb->start_frame = uurb->start_frame;
	as->urb->number_of_packets = uurb->number_of_packets;
	if (uurb->type == USBDEVFS_URB_TYPE_ISO ||
			ps->dev->speed == USB_SPEED_HIGH)
		as->urb->interval = 1 << min(15, ep->desc.bInterval - 1);
	else
		as->urb->interval = ep->desc.bInterval;
        as->urb->context = as;
        as->urb->complete = async_completed;
	for (totlen = u = 0; u < uurb->number_of_packets; u++) {
		as->urb->iso_frame_desc[u].offset = totlen;
		as->urb->iso_frame_desc[u].length = isopkt[u].length;
		totlen += isopkt[u].length;
	}
	kfree(isopkt);
	as->ps = ps;
        as->userurb = arg;
	if (uurb->endpoint & USB_DIR_IN)
		as->userbuffer = uurb->buffer;
	else
		as->userbuffer = NULL;
	as->signr = uurb->signr;
	as->ifnum = ifnum;
	as->pid = get_pid(task_pid(current));
	as->uid = current->uid;
	as->euid = current->euid;
	security_task_getsecid(current, &as->secid);
	if (!is_in) {
		if (copy_from_user(as->urb->transfer_buffer, uurb->buffer,
				as->urb->transfer_buffer_length)) {
			free_async(as);
			return -EFAULT;
		}
	}
	snoop_urb(as->urb, as->userurb);
        async_newpending(as);
        if ((ret = usb_submit_urb(as->urb, GFP_KERNEL))) {
		dev_printk(KERN_DEBUG, &ps->dev->dev, "usbfs: usb_submit_urb returned %d\n", ret);
                async_removepending(as);
                free_async(as);
                return ret;
        }
        return 0;
}

static int proc_submiturb(struct dev_state *ps, void __user *arg)
{
	struct usbdevfs_urb uurb;

	if (copy_from_user(&uurb, arg, sizeof(uurb)))
		return -EFAULT;

	return proc_do_submiturb(ps, &uurb, (((struct usbdevfs_urb __user *)arg)->iso_frame_desc), arg);
}

static int proc_unlinkurb(struct dev_state *ps, void __user *arg)
{
	struct async *as;

	as = async_getpending(ps, arg);
	if (!as)
		return -EINVAL;
	usb_kill_urb(as->urb);
	return 0;
}

static int processcompl(struct async *as, void __user * __user *arg)
{
	struct urb *urb = as->urb;
	struct usbdevfs_urb __user *userurb = as->userurb;
	void __user *addr = as->userurb;
	unsigned int i;

	if (as->userbuffer)
		if (copy_to_user(as->userbuffer, urb->transfer_buffer, urb->transfer_buffer_length))
			return -EFAULT;
	if (put_user(as->status, &userurb->status))
		return -EFAULT;
	if (put_user(urb->actual_length, &userurb->actual_length))
		return -EFAULT;
	if (put_user(urb->error_count, &userurb->error_count))
		return -EFAULT;

	if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
		for (i = 0; i < urb->number_of_packets; i++) {
			if (put_user(urb->iso_frame_desc[i].actual_length,
				     &userurb->iso_frame_desc[i].actual_length))
				return -EFAULT;
			if (put_user(urb->iso_frame_desc[i].status,
				     &userurb->iso_frame_desc[i].status))
				return -EFAULT;
		}
	}

	free_async(as);

	if (put_user(addr, (void __user * __user *)arg))
		return -EFAULT;
	return 0;
}

static struct async* reap_as(struct dev_state *ps)
{
        DECLARE_WAITQUEUE(wait, current);
	struct async *as = NULL;
	struct usb_device *dev = ps->dev;

	add_wait_queue(&ps->wait, &wait);
	for (;;) {
		__set_current_state(TASK_INTERRUPTIBLE);
		if ((as = async_getcompleted(ps)))
			break;
		if (signal_pending(current))
			break;
		usb_unlock_device(dev);
		schedule();
		usb_lock_device(dev);
	}
	remove_wait_queue(&ps->wait, &wait);
	set_current_state(TASK_RUNNING);
	return as;
}

static int proc_reapurb(struct dev_state *ps, void __user *arg)
{
	struct async *as = reap_as(ps);
	if (as)
		return processcompl(as, (void __user * __user *)arg);
	if (signal_pending(current))
		return -EINTR;
	return -EIO;
}

static int proc_reapurbnonblock(struct dev_state *ps, void __user *arg)
{
	struct async *as;

	if (!(as = async_getcompleted(ps)))
		return -EAGAIN;
	return processcompl(as, (void __user * __user *)arg);
}

#ifdef CONFIG_COMPAT

static int get_urb32(struct usbdevfs_urb *kurb,
		     struct usbdevfs_urb32 __user *uurb)
{
	__u32  uptr;
	if (get_user(kurb->type, &uurb->type) ||
	    __get_user(kurb->endpoint, &uurb->endpoint) ||
	    __get_user(kurb->status, &uurb->status) ||
	    __get_user(kurb->flags, &uurb->flags) ||
	    __get_user(kurb->buffer_length, &uurb->buffer_length) ||
	    __get_user(kurb->actual_length, &uurb->actual_length) ||
	    __get_user(kurb->start_frame, &uurb->start_frame) ||
	    __get_user(kurb->number_of_packets, &uurb->number_of_packets) ||
	    __get_user(kurb->error_count, &uurb->error_count) ||
	    __get_user(kurb->signr, &uurb->signr))
		return -EFAULT;

	if (__get_user(uptr, &uurb->buffer))
		return -EFAULT;
	kurb->buffer = compat_ptr(uptr);
	if (__get_user(uptr, &uurb->buffer))
		return -EFAULT;
	kurb->usercontext = compat_ptr(uptr);

	return 0;
}

static int proc_submiturb_compat(struct dev_state *ps, void __user *arg)
{
	struct usbdevfs_urb uurb;

	if (get_urb32(&uurb,(struct usbdevfs_urb32 __user *)arg))
		return -EFAULT;

	return proc_do_submiturb(ps, &uurb, ((struct usbdevfs_urb32 __user *)arg)->iso_frame_desc, arg);
}

static int processcompl_compat(struct async *as, void __user * __user *arg)
{
	struct urb *urb = as->urb;
	struct usbdevfs_urb32 __user *userurb = as->userurb;
	void __user *addr = as->userurb;
	unsigned int i;

	if (as->userbuffer)
		if (copy_to_user(as->userbuffer, urb->transfer_buffer, urb->transfer_buffer_length))
			return -EFAULT;
	if (put_user(as->status, &userurb->status))
		return -EFAULT;
	if (put_user(urb->actual_length, &userurb->actual_length))
		return -EFAULT;
	if (put_user(urb->error_count, &userurb->error_count))
		return -EFAULT;

	if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
		for (i = 0; i < urb->number_of_packets; i++) {
			if (put_user(urb->iso_frame_desc[i].actual_length,
				     &userurb->iso_frame_desc[i].actual_length))
				return -EFAULT;
			if (put_user(urb->iso_frame_desc[i].status,
				     &userurb->iso_frame_desc[i].status))
				return -EFAULT;
		}
	}

	free_async(as);
	if (put_user(ptr_to_compat(addr), (u32 __user *)arg))
		return -EFAULT;
	return 0;
}

static int proc_reapurb_compat(struct dev_state *ps, void __user *arg)
{
	struct async *as = reap_as(ps);
	if (as)
		return processcompl_compat(as, (void __user * __user *)arg);
	if (signal_pending(current))
		return -EINTR;
	return -EIO;
}

static int proc_reapurbnonblock_compat(struct dev_state *ps, void __user *arg)
{
	struct async *as;

	if (!(as = async_getcompleted(ps)))
		return -EAGAIN;
	return processcompl_compat(as, (void __user * __user *)arg);
}

#endif

static int proc_disconnectsignal(struct dev_state *ps, void __user *arg)
{
	struct usbdevfs_disconnectsignal ds;

	if (copy_from_user(&ds, arg, sizeof(ds)))
		return -EFAULT;
	if (ds.signr != 0 && (ds.signr < SIGRTMIN || ds.signr > SIGRTMAX))
		return -EINVAL;
	ps->discsignr = ds.signr;
	ps->disccontext = ds.context;
	return 0;
}

static int proc_claiminterface(struct dev_state *ps, void __user *arg)
{
	unsigned int ifnum;

	if (get_user(ifnum, (unsigned int __user *)arg))
		return -EFAULT;
	return claimintf(ps, ifnum);
}

static int proc_releaseinterface(struct dev_state *ps, void __user *arg)
{
	unsigned int ifnum;
	int ret;

	if (get_user(ifnum, (unsigned int __user *)arg))
		return -EFAULT;
	if ((ret = releaseintf(ps, ifnum)) < 0)
		return ret;
	destroy_async_on_interface (ps, ifnum);
	return 0;
}

static int proc_ioctl(struct dev_state *ps, struct usbdevfs_ioctl *ctl)
{
	int			size;
	void			*buf = NULL;
	int			retval = 0;
	struct usb_interface    *intf = NULL;
	struct usb_driver       *driver = NULL;

	/* alloc buffer */
	if ((size = _IOC_SIZE (ctl->ioctl_code)) > 0) {
		if ((buf = kmalloc (size, GFP_KERNEL)) == NULL)
			return -ENOMEM;
		if ((_IOC_DIR(ctl->ioctl_code) & _IOC_WRITE)) {
			if (copy_from_user (buf, ctl->data, size)) {
				kfree(buf);
				return -EFAULT;
			}
		} else {
			memset (buf, 0, size);
		}
	}

	if (!connected(ps)) {
		kfree(buf);
		return -ENODEV;
	}

	if (ps->dev->state != USB_STATE_CONFIGURED)
		retval = -EHOSTUNREACH;
	else if (!(intf = usb_ifnum_to_if (ps->dev, ctl->ifno)))
               retval = -EINVAL;
	else switch (ctl->ioctl_code) {

	/* disconnect kernel driver from interface */
	case USBDEVFS_DISCONNECT:
		if (intf->dev.driver) {
			driver = to_usb_driver(intf->dev.driver);
			dev_dbg (&intf->dev, "disconnect by usbfs\n");
			usb_driver_release_interface(driver, intf);
		} else
			retval = -ENODATA;
		break;

	/* let kernel drivers try to (re)bind to the interface */
	case USBDEVFS_CONNECT:
		if (!intf->dev.driver)
			retval = device_attach(&intf->dev);
		else
			retval = -EBUSY;
		break;

	/* talk directly to the interface's driver */
	default:
		if (intf->dev.driver)
			driver = to_usb_driver(intf->dev.driver);
		if (driver == NULL || driver->ioctl == NULL) {
			retval = -ENOTTY;
		} else {
			retval = driver->ioctl (intf, ctl->ioctl_code, buf);
			if (retval == -ENOIOCTLCMD)
				retval = -ENOTTY;
		}
	}

	/* cleanup and return */
	if (retval >= 0
			&& (_IOC_DIR (ctl->ioctl_code) & _IOC_READ) != 0
			&& size > 0
			&& copy_to_user (ctl->data, buf, size) != 0)
		retval = -EFAULT;

	kfree(buf);
	return retval;
}

static int proc_ioctl_default(struct dev_state *ps, void __user *arg)
{
	struct usbdevfs_ioctl	ctrl;

	if (copy_from_user(&ctrl, arg, sizeof (ctrl)))
		return -EFAULT;
	return proc_ioctl(ps, &ctrl);
}

#ifdef CONFIG_COMPAT
static int proc_ioctl_compat(struct dev_state *ps, compat_uptr_t arg)
{
	struct usbdevfs_ioctl32 __user *uioc;
	struct usbdevfs_ioctl ctrl;
	u32 udata;

	uioc = compat_ptr((long)arg);
	if (get_user(ctrl.ifno, &uioc->ifno) ||
	    get_user(ctrl.ioctl_code, &uioc->ioctl_code) ||
	    __get_user(udata, &uioc->data))
		return -EFAULT;
	ctrl.data = compat_ptr(udata);

	return proc_ioctl(ps, &ctrl);
}
#endif

/*
 * NOTE:  All requests here that have interface numbers as parameters
 * are assuming that somehow the configuration has been prevented from
 * changing.  But there's no mechanism to ensure that...
 */
static int usbdev_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
{
	struct dev_state *ps = file->private_data;
	struct usb_device *dev = ps->dev;
	void __user *p = (void __user *)arg;
	int ret = -ENOTTY;

	if (!(file->f_mode & FMODE_WRITE))
		return -EPERM;
	usb_lock_device(dev);
	if (!connected(ps)) {
		usb_unlock_device(dev);
		return -ENODEV;
	}

	switch (cmd) {
	case USBDEVFS_CONTROL:
		snoop(&dev->dev, "%s: CONTROL\n", __FUNCTION__);
		ret = proc_control(ps, p);
		if (ret >= 0)
			inode->i_mtime = CURRENT_TIME;
		break;

	case USBDEVFS_BULK:
		snoop(&dev->dev, "%s: BULK\n", __FUNCTION__);
		ret = proc_bulk(ps, p);
		if (ret >= 0)
			inode->i_mtime = CURRENT_TIME;
		break;

	case USBDEVFS_RESETEP:
		snoop(&dev->dev, "%s: RESETEP\n", __FUNCTION__);
		ret = proc_resetep(ps, p);
		if (ret >= 0)
			inode->i_mtime = CURRENT_TIME;
		break;

	case USBDEVFS_RESET:
		snoop(&dev->dev, "%s: RESET\n", __FUNCTION__);
		ret = proc_resetdevice(ps);
		break;

	case USBDEVFS_CLEAR_HALT:
		snoop(&dev->dev, "%s: CLEAR_HALT\n", __FUNCTION__);
		ret = proc_clearhalt(ps, p);
		if (ret >= 0)
			inode->i_mtime = CURRENT_TIME;
		break;

	case USBDEVFS_GETDRIVER:
		snoop(&dev->dev, "%s: GETDRIVER\n", __FUNCTION__);
		ret = proc_getdriver(ps, p);
		break;

	case USBDEVFS_CONNECTINFO:
		snoop(&dev->dev, "%s: CONNECTINFO\n", __FUNCTION__);
		ret = proc_connectinfo(ps, p);
		break;

	case USBDEVFS_SETINTERFACE:
		snoop(&dev->dev, "%s: SETINTERFACE\n", __FUNCTION__);
		ret = proc_setintf(ps, p);
		break;

	case USBDEVFS_SETCONFIGURATION:
		snoop(&dev->dev, "%s: SETCONFIGURATION\n", __FUNCTION__);
		ret = proc_setconfig(ps, p);
		break;

	case USBDEVFS_SUBMITURB:
		snoop(&dev->dev, "%s: SUBMITURB\n", __FUNCTION__);
		ret = proc_submiturb(ps, p);
		if (ret >= 0)
			inode->i_mtime = CURRENT_TIME;
		break;

#ifdef CONFIG_COMPAT

	case USBDEVFS_SUBMITURB32:
		snoop(&dev->dev, "%s: SUBMITURB32\n", __FUNCTION__);
		ret = proc_submiturb_compat(ps, p);
		if (ret >= 0)
			inode->i_mtime = CURRENT_TIME;
		break;

	case USBDEVFS_REAPURB32:
		snoop(&dev->dev, "%s: REAPURB32\n", __FUNCTION__);
		ret = proc_reapurb_compat(ps, p);
		break;

	case USBDEVFS_REAPURBNDELAY32:
		snoop(&dev->dev, "%s: REAPURBDELAY32\n", __FUNCTION__);
		ret = proc_reapurbnonblock_compat(ps, p);
		break;

	case USBDEVFS_IOCTL32:
		snoop(&dev->dev, "%s: IOCTL\n", __FUNCTION__);
		ret = proc_ioctl_compat(ps, ptr_to_compat(p));
		break;
#endif

	case USBDEVFS_DISCARDURB:
		snoop(&dev->dev, "%s: DISCARDURB\n", __FUNCTION__);
		ret = proc_unlinkurb(ps, p);
		break;

	case USBDEVFS_REAPURB:
		snoop(&dev->dev, "%s: REAPURB\n", __FUNCTION__);
		ret = proc_reapurb(ps, p);
		break;

	case USBDEVFS_REAPURBNDELAY:
		snoop(&dev->dev, "%s: REAPURBDELAY\n", __FUNCTION__);
		ret = proc_reapurbnonblock(ps, p);
		break;

	case USBDEVFS_DISCSIGNAL:
		snoop(&dev->dev, "%s: DISCSIGNAL\n", __FUNCTION__);
		ret = proc_disconnectsignal(ps, p);
		break;

	case USBDEVFS_CLAIMINTERFACE:
		snoop(&dev->dev, "%s: CLAIMINTERFACE\n", __FUNCTION__);
		ret = proc_claiminterface(ps, p);
		break;

	case USBDEVFS_RELEASEINTERFACE:
		snoop(&dev->dev, "%s: RELEASEINTERFACE\n", __FUNCTION__);
		ret = proc_releaseinterface(ps, p);
		break;

	case USBDEVFS_IOCTL:
		snoop(&dev->dev, "%s: IOCTL\n", __FUNCTION__);
		ret = proc_ioctl_default(ps, p);
		break;
	}
	usb_unlock_device(dev);
	if (ret >= 0)
		inode->i_atime = CURRENT_TIME;
	return ret;
}

/* No kernel lock - fine */
static unsigned int usbdev_poll(struct file *file, struct poll_table_struct *wait)
{
	struct dev_state *ps = file->private_data;
	unsigned int mask = 0;

	poll_wait(file, &ps->wait, wait);
	if (file->f_mode & FMODE_WRITE && !list_empty(&ps->async_completed))
		mask |= POLLOUT | POLLWRNORM;
	if (!connected(ps))
		mask |= POLLERR | POLLHUP;
	return mask;
}

const struct file_operations usbdev_file_operations = {
	.owner = 	THIS_MODULE,
	.llseek =	usbdev_lseek,
	.read =		usbdev_read,
	.poll =		usbdev_poll,
	.ioctl =	usbdev_ioctl,
	.open =		usbdev_open,
	.release =	usbdev_release,
};

#ifdef CONFIG_USB_DEVICE_CLASS
static struct class *usb_classdev_class;

static int usb_classdev_add(struct usb_device *dev)
{
	int minor = ((dev->bus->busnum-1) * 128) + (dev->devnum-1);

	dev->usb_classdev = device_create(usb_classdev_class, &dev->dev,
				MKDEV(USB_DEVICE_MAJOR, minor),
				"usbdev%d.%d", dev->bus->busnum, dev->devnum);
	if (IS_ERR(dev->usb_classdev))
		return PTR_ERR(dev->usb_classdev);

	return 0;
}

static void usb_classdev_remove(struct usb_device *dev)
{
	device_unregister(dev->usb_classdev);
}

static int usb_classdev_notify(struct notifier_block *self,
			       unsigned long action, void *dev)
{
	switch (action) {
	case USB_DEVICE_ADD:
		if (usb_classdev_add(dev))
			return NOTIFY_BAD;
		break;
	case USB_DEVICE_REMOVE:
		usb_classdev_remove(dev);
		break;
	}
	return NOTIFY_OK;
}

static struct notifier_block usbdev_nb = {
	.notifier_call = 	usb_classdev_notify,
};
#endif

static struct cdev usb_device_cdev;

int __init usb_devio_init(void)
{
	int retval;

	retval = register_chrdev_region(USB_DEVICE_DEV, USB_DEVICE_MAX,
			"usb_device");
	if (retval) {
		err("unable to register minors for usb_device");
		goto out;
	}
	cdev_init(&usb_device_cdev, &usbdev_file_operations);
	retval = cdev_add(&usb_device_cdev, USB_DEVICE_DEV, USB_DEVICE_MAX);
	if (retval) {
		err("unable to get usb_device major %d", USB_DEVICE_MAJOR);
		goto error_cdev;
	}
#ifdef CONFIG_USB_DEVICE_CLASS
	usb_classdev_class = class_create(THIS_MODULE, "usb_device");
	if (IS_ERR(usb_classdev_class)) {
		err("unable to register usb_device class");
		retval = PTR_ERR(usb_classdev_class);
		cdev_del(&usb_device_cdev);
		usb_classdev_class = NULL;
		goto out;
	}

	usb_register_notify(&usbdev_nb);
#endif
out:
	return retval;

error_cdev:
	unregister_chrdev_region(USB_DEVICE_DEV, USB_DEVICE_MAX);
	goto out;
}

void usb_devio_cleanup(void)
{
#ifdef CONFIG_USB_DEVICE_CLASS
	usb_unregister_notify(&usbdev_nb);
	class_destroy(usb_classdev_class);
#endif
	cdev_del(&usb_device_cdev);
	unregister_chrdev_region(USB_DEVICE_DEV, USB_DEVICE_MAX);
}