summaryrefslogtreecommitdiff
path: root/include/linux/usb.h
blob: 25f8e62a30ecac5dcf9463102966e4b5d7938a6c (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
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __LINUX_USB_H
#define __LINUX_USB_H

#include <linux/mod_devicetable.h>
#include <linux/usb/ch9.h>

#define USB_MAJOR			180
#define USB_DEVICE_MAJOR		189


#ifdef __KERNEL__

#include <linux/errno.h>        /* for -ENODEV */
#include <linux/delay.h>	/* for mdelay() */
#include <linux/interrupt.h>	/* for in_interrupt() */
#include <linux/list.h>		/* for struct list_head */
#include <linux/kref.h>		/* for struct kref */
#include <linux/device.h>	/* for struct device */
#include <linux/fs.h>		/* for struct file_operations */
#include <linux/completion.h>	/* for struct completion */
#include <linux/sched.h>	/* for current && schedule_timeout */
#include <linux/mutex.h>	/* for struct mutex */
#include <linux/pm_runtime.h>	/* for runtime PM */

struct usb_device;
struct usb_driver;
struct wusb_dev;

/*-------------------------------------------------------------------------*/

/*
 * Host-side wrappers for standard USB descriptors ... these are parsed
 * from the data provided by devices.  Parsing turns them from a flat
 * sequence of descriptors into a hierarchy:
 *
 *  - devices have one (usually) or more configs;
 *  - configs have one (often) or more interfaces;
 *  - interfaces have one (usually) or more settings;
 *  - each interface setting has zero or (usually) more endpoints.
 *  - a SuperSpeed endpoint has a companion descriptor
 *
 * And there might be other descriptors mixed in with those.
 *
 * Devices may also have class-specific or vendor-specific descriptors.
 */

struct ep_device;

/**
 * struct usb_host_endpoint - host-side endpoint descriptor and queue
 * @desc: descriptor for this endpoint, wMaxPacketSize in native byteorder
 * @ss_ep_comp: SuperSpeed companion descriptor for this endpoint
 * @ssp_isoc_ep_comp: SuperSpeedPlus isoc companion descriptor for this endpoint
 * @urb_list: urbs queued to this endpoint; maintained by usbcore
 * @hcpriv: for use by HCD; typically holds hardware dma queue head (QH)
 *	with one or more transfer descriptors (TDs) per urb
 * @ep_dev: ep_device for sysfs info
 * @extra: descriptors following this endpoint in the configuration
 * @extralen: how many bytes of "extra" are valid
 * @enabled: URBs may be submitted to this endpoint
 * @streams: number of USB-3 streams allocated on the endpoint
 *
 * USB requests are always queued to a given endpoint, identified by a
 * descriptor within an active interface in a given USB configuration.
 */
struct usb_host_endpoint {
	struct usb_endpoint_descriptor		desc;
	struct usb_ss_ep_comp_descriptor	ss_ep_comp;
	struct usb_ssp_isoc_ep_comp_descriptor	ssp_isoc_ep_comp;
	struct list_head		urb_list;
	void				*hcpriv;
	struct ep_device		*ep_dev;	/* For sysfs info */

	unsigned char *extra;   /* Extra descriptors */
	int extralen;
	int enabled;
	int streams;
};

/* host-side wrapper for one interface setting's parsed descriptors */
struct usb_host_interface {
	struct usb_interface_descriptor	desc;

	int extralen;
	unsigned char *extra;   /* Extra descriptors */

	/* array of desc.bNumEndpoints endpoints associated with this
	 * interface setting.  these will be in no particular order.
	 */
	struct usb_host_endpoint *endpoint;

	char *string;		/* iInterface string, if present */
};

enum usb_interface_condition {
	USB_INTERFACE_UNBOUND = 0,
	USB_INTERFACE_BINDING,
	USB_INTERFACE_BOUND,
	USB_INTERFACE_UNBINDING,
};

int __must_check
usb_find_common_endpoints(struct usb_host_interface *alt,
		struct usb_endpoint_descriptor **bulk_in,
		struct usb_endpoint_descriptor **bulk_out,
		struct usb_endpoint_descriptor **int_in,
		struct usb_endpoint_descriptor **int_out);

int __must_check
usb_find_common_endpoints_reverse(struct usb_host_interface *alt,
		struct usb_endpoint_descriptor **bulk_in,
		struct usb_endpoint_descriptor **bulk_out,
		struct usb_endpoint_descriptor **int_in,
		struct usb_endpoint_descriptor **int_out);

static inline int __must_check
usb_find_bulk_in_endpoint(struct usb_host_interface *alt,
		struct usb_endpoint_descriptor **bulk_in)
{
	return usb_find_common_endpoints(alt, bulk_in, NULL, NULL, NULL);
}

static inline int __must_check
usb_find_bulk_out_endpoint(struct usb_host_interface *alt,
		struct usb_endpoint_descriptor **bulk_out)
{
	return usb_find_common_endpoints(alt, NULL, bulk_out, NULL, NULL);
}

static inline int __must_check
usb_find_int_in_endpoint(struct usb_host_interface *alt,
		struct usb_endpoint_descriptor **int_in)
{
	return usb_find_common_endpoints(alt, NULL, NULL, int_in, NULL);
}

static inline int __must_check
usb_find_int_out_endpoint(struct usb_host_interface *alt,
		struct usb_endpoint_descriptor **int_out)
{
	return usb_find_common_endpoints(alt, NULL, NULL, NULL, int_out);
}

static inline int __must_check
usb_find_last_bulk_in_endpoint(struct usb_host_interface *alt,
		struct usb_endpoint_descriptor **bulk_in)
{
	return usb_find_common_endpoints_reverse(alt, bulk_in, NULL, NULL, NULL);
}

static inline int __must_check
usb_find_last_bulk_out_endpoint(struct usb_host_interface *alt,
		struct usb_endpoint_descriptor **bulk_out)
{
	return usb_find_common_endpoints_reverse(alt, NULL, bulk_out, NULL, NULL);
}

static inline int __must_check
usb_find_last_int_in_endpoint(struct usb_host_interface *alt,
		struct usb_endpoint_descriptor **int_in)
{
	return usb_find_common_endpoints_reverse(alt, NULL, NULL, int_in, NULL);
}

static inline int __must_check
usb_find_last_int_out_endpoint(struct usb_host_interface *alt,
		struct usb_endpoint_descriptor **int_out)
{
	return usb_find_common_endpoints_reverse(alt, NULL, NULL, NULL, int_out);
}

enum usb_wireless_status {
	USB_WIRELESS_STATUS_NA = 0,
	USB_WIRELESS_STATUS_DISCONNECTED,
	USB_WIRELESS_STATUS_CONNECTED,
};

/**
 * struct usb_interface - what usb device drivers talk to
 * @altsetting: array of interface structures, one for each alternate
 *	setting that may be selected.  Each one includes a set of
 *	endpoint configurations.  They will be in no particular order.
 * @cur_altsetting: the current altsetting.
 * @num_altsetting: number of altsettings defined.
 * @intf_assoc: interface association descriptor
 * @minor: the minor number assigned to this interface, if this
 *	interface is bound to a driver that uses the USB major number.
 *	If this interface does not use the USB major, this field should
 *	be unused.  The driver should set this value in the probe()
 *	function of the driver, after it has been assigned a minor
 *	number from the USB core by calling usb_register_dev().
 * @condition: binding state of the interface: not bound, binding
 *	(in probe()), bound to a driver, or unbinding (in disconnect())
 * @sysfs_files_created: sysfs attributes exist
 * @ep_devs_created: endpoint child pseudo-devices exist
 * @unregistering: flag set when the interface is being unregistered
 * @needs_remote_wakeup: flag set when the driver requires remote-wakeup
 *	capability during autosuspend.
 * @needs_altsetting0: flag set when a set-interface request for altsetting 0
 *	has been deferred.
 * @needs_binding: flag set when the driver should be re-probed or unbound
 *	following a reset or suspend operation it doesn't support.
 * @authorized: This allows to (de)authorize individual interfaces instead
 *	a whole device in contrast to the device authorization.
 * @wireless_status: if the USB device uses a receiver/emitter combo, whether
 *	the emitter is connected.
 * @wireless_status_work: Used for scheduling wireless status changes
 *	from atomic context.
 * @dev: driver model's view of this device
 * @usb_dev: if an interface is bound to the USB major, this will point
 *	to the sysfs representation for that device.
 * @reset_ws: Used for scheduling resets from atomic context.
 * @resetting_device: USB core reset the device, so use alt setting 0 as
 *	current; needs bandwidth alloc after reset.
 *
 * USB device drivers attach to interfaces on a physical device.  Each
 * interface encapsulates a single high level function, such as feeding
 * an audio stream to a speaker or reporting a change in a volume control.
 * Many USB devices only have one interface.  The protocol used to talk to
 * an interface's endpoints can be defined in a usb "class" specification,
 * or by a product's vendor.  The (default) control endpoint is part of
 * every interface, but is never listed among the interface's descriptors.
 *
 * The driver that is bound to the interface can use standard driver model
 * calls such as dev_get_drvdata() on the dev member of this structure.
 *
 * Each interface may have alternate settings.  The initial configuration
 * of a device sets altsetting 0, but the device driver can change
 * that setting using usb_set_interface().  Alternate settings are often
 * used to control the use of periodic endpoints, such as by having
 * different endpoints use different amounts of reserved USB bandwidth.
 * All standards-conformant USB devices that use isochronous endpoints
 * will use them in non-default settings.
 *
 * The USB specification says that alternate setting numbers must run from
 * 0 to one less than the total number of alternate settings.  But some
 * devices manage to mess this up, and the structures aren't necessarily
 * stored in numerical order anyhow.  Use usb_altnum_to_altsetting() to
 * look up an alternate setting in the altsetting array based on its number.
 */
struct usb_interface {
	/* array of alternate settings for this interface,
	 * stored in no particular order */
	struct usb_host_interface *altsetting;

	struct usb_host_interface *cur_altsetting;	/* the currently
					 * active alternate setting */
	unsigned num_altsetting;	/* number of alternate settings */

	/* If there is an interface association descriptor then it will list
	 * the associated interfaces */
	struct usb_interface_assoc_descriptor *intf_assoc;

	int minor;			/* minor number this interface is
					 * bound to */
	enum usb_interface_condition condition;		/* state of binding */
	unsigned sysfs_files_created:1;	/* the sysfs attributes exist */
	unsigned ep_devs_created:1;	/* endpoint "devices" exist */
	unsigned unregistering:1;	/* unregistration is in progress */
	unsigned needs_remote_wakeup:1;	/* driver requires remote wakeup */
	unsigned needs_altsetting0:1;	/* switch to altsetting 0 is pending */
	unsigned needs_binding:1;	/* needs delayed unbind/rebind */
	unsigned resetting_device:1;	/* true: bandwidth alloc after reset */
	unsigned authorized:1;		/* used for interface authorization */
	enum usb_wireless_status wireless_status;
	struct work_struct wireless_status_work;

	struct device dev;		/* interface specific device info */
	struct device *usb_dev;
	struct work_struct reset_ws;	/* for resets in atomic context */
};

#define to_usb_interface(__dev)	container_of_const(__dev, struct usb_interface, dev)

static inline void *usb_get_intfdata(struct usb_interface *intf)
{
	return dev_get_drvdata(&intf->dev);
}

/**
 * usb_set_intfdata() - associate driver-specific data with an interface
 * @intf: USB interface
 * @data: driver data
 *
 * Drivers can use this function in their probe() callbacks to associate
 * driver-specific data with an interface.
 *
 * Note that there is generally no need to clear the driver-data pointer even
 * if some drivers do so for historical or implementation-specific reasons.
 */
static inline void usb_set_intfdata(struct usb_interface *intf, void *data)
{
	dev_set_drvdata(&intf->dev, data);
}

struct usb_interface *usb_get_intf(struct usb_interface *intf);
void usb_put_intf(struct usb_interface *intf);

/* Hard limit */
#define USB_MAXENDPOINTS	30
/* this maximum is arbitrary */
#define USB_MAXINTERFACES	32
#define USB_MAXIADS		(USB_MAXINTERFACES/2)

bool usb_check_bulk_endpoints(
		const struct usb_interface *intf, const u8 *ep_addrs);
bool usb_check_int_endpoints(
		const struct usb_interface *intf, const u8 *ep_addrs);

/*
 * USB Resume Timer: Every Host controller driver should drive the resume
 * signalling on the bus for the amount of time defined by this macro.
 *
 * That way we will have a 'stable' behavior among all HCDs supported by Linux.
 *
 * Note that the USB Specification states we should drive resume for *at least*
 * 20 ms, but it doesn't give an upper bound. This creates two possible
 * situations which we want to avoid:
 *
 * (a) sometimes an msleep(20) might expire slightly before 20 ms, which causes
 * us to fail USB Electrical Tests, thus failing Certification
 *
 * (b) Some (many) devices actually need more than 20 ms of resume signalling,
 * and while we can argue that's against the USB Specification, we don't have
 * control over which devices a certification laboratory will be using for
 * certification. If CertLab uses a device which was tested against Windows and
 * that happens to have relaxed resume signalling rules, we might fall into
 * situations where we fail interoperability and electrical tests.
 *
 * In order to avoid both conditions, we're using a 40 ms resume timeout, which
 * should cope with both LPJ calibration errors and devices not following every
 * detail of the USB Specification.
 */
#define USB_RESUME_TIMEOUT	40 /* ms */

/**
 * struct usb_interface_cache - long-term representation of a device interface
 * @num_altsetting: number of altsettings defined.
 * @ref: reference counter.
 * @altsetting: variable-length array of interface structures, one for
 *	each alternate setting that may be selected.  Each one includes a
 *	set of endpoint configurations.  They will be in no particular order.
 *
 * These structures persist for the lifetime of a usb_device, unlike
 * struct usb_interface (which persists only as long as its configuration
 * is installed).  The altsetting arrays can be accessed through these
 * structures at any time, permitting comparison of configurations and
 * providing support for the /sys/kernel/debug/usb/devices pseudo-file.
 */
struct usb_interface_cache {
	unsigned num_altsetting;	/* number of alternate settings */
	struct kref ref;		/* reference counter */

	/* variable-length array of alternate settings for this interface,
	 * stored in no particular order */
	struct usb_host_interface altsetting[];
};
#define	ref_to_usb_interface_cache(r) \
		container_of(r, struct usb_interface_cache, ref)
#define	altsetting_to_usb_interface_cache(a) \
		container_of(a, struct usb_interface_cache, altsetting[0])

/**
 * struct usb_host_config - representation of a device's configuration
 * @desc: the device's configuration descriptor.
 * @string: pointer to the cached version of the iConfiguration string, if
 *	present for this configuration.
 * @intf_assoc: list of any interface association descriptors in this config
 * @interface: array of pointers to usb_interface structures, one for each
 *	interface in the configuration.  The number of interfaces is stored
 *	in desc.bNumInterfaces.  These pointers are valid only while the
 *	configuration is active.
 * @intf_cache: array of pointers to usb_interface_cache structures, one
 *	for each interface in the configuration.  These structures exist
 *	for the entire life of the device.
 * @extra: pointer to buffer containing all extra descriptors associated
 *	with this configuration (those preceding the first interface
 *	descriptor).
 * @extralen: length of the extra descriptors buffer.
 *
 * USB devices may have multiple configurations, but only one can be active
 * at any time.  Each encapsulates a different operational environment;
 * for example, a dual-speed device would have separate configurations for
 * full-speed and high-speed operation.  The number of configurations
 * available is stored in the device descriptor as bNumConfigurations.
 *
 * A configuration can contain multiple interfaces.  Each corresponds to
 * a different function of the USB device, and all are available whenever
 * the configuration is active.  The USB standard says that interfaces
 * are supposed to be numbered from 0 to desc.bNumInterfaces-1, but a lot
 * of devices get this wrong.  In addition, the interface array is not
 * guaranteed to be sorted in numerical order.  Use usb_ifnum_to_if() to
 * look up an interface entry based on its number.
 *
 * Device drivers should not attempt to activate configurations.  The choice
 * of which configuration to install is a policy decision based on such
 * considerations as available power, functionality provided, and the user's
 * desires (expressed through userspace tools).  However, drivers can call
 * usb_reset_configuration() to reinitialize the current configuration and
 * all its interfaces.
 */
struct usb_host_config {
	struct usb_config_descriptor	desc;

	char *string;		/* iConfiguration string, if present */

	/* List of any Interface Association Descriptors in this
	 * configuration. */
	struct usb_interface_assoc_descriptor *intf_assoc[USB_MAXIADS];

	/* the interfaces associated with this configuration,
	 * stored in no particular order */
	struct usb_interface *interface[USB_MAXINTERFACES];

	/* Interface information available even when this is not the
	 * active configuration */
	struct usb_interface_cache *intf_cache[USB_MAXINTERFACES];

	unsigned char *extra;   /* Extra descriptors */
	int extralen;
};

/* USB2.0 and USB3.0 device BOS descriptor set */
struct usb_host_bos {
	struct usb_bos_descriptor	*desc;

	/* wireless cap descriptor is handled by wusb */
	struct usb_ext_cap_descriptor	*ext_cap;
	struct usb_ss_cap_descriptor	*ss_cap;
	struct usb_ssp_cap_descriptor	*ssp_cap;
	struct usb_ss_container_id_descriptor	*ss_id;
	struct usb_ptm_cap_descriptor	*ptm_cap;
};

int __usb_get_extra_descriptor(char *buffer, unsigned size,
	unsigned char type, void **ptr, size_t min);
#define usb_get_extra_descriptor(ifpoint, type, ptr) \
				__usb_get_extra_descriptor((ifpoint)->extra, \
				(ifpoint)->extralen, \
				type, (void **)ptr, sizeof(**(ptr)))

/* ----------------------------------------------------------------------- */

/* USB device number allocation bitmap */
struct usb_devmap {
	unsigned long devicemap[128 / (8*sizeof(unsigned long))];
};

/*
 * Allocated per bus (tree of devices) we have:
 */
struct usb_bus {
	struct device *controller;	/* host side hardware */
	struct device *sysdev;		/* as seen from firmware or bus */
	int busnum;			/* Bus number (in order of reg) */
	const char *bus_name;		/* stable id (PCI slot_name etc) */
	u8 uses_pio_for_control;	/*
					 * Does the host controller use PIO
					 * for control transfers?
					 */
	u8 otg_port;			/* 0, or number of OTG/HNP port */
	unsigned is_b_host:1;		/* true during some HNP roleswitches */
	unsigned b_hnp_enable:1;	/* OTG: did A-Host enable HNP? */
	unsigned no_stop_on_short:1;    /*
					 * Quirk: some controllers don't stop
					 * the ep queue on a short transfer
					 * with the URB_SHORT_NOT_OK flag set.
					 */
	unsigned no_sg_constraint:1;	/* no sg constraint */
	unsigned sg_tablesize;		/* 0 or largest number of sg list entries */

	int devnum_next;		/* Next open device number in
					 * round-robin allocation */
	struct mutex devnum_next_mutex; /* devnum_next mutex */

	struct usb_devmap devmap;	/* device address allocation map */
	struct usb_device *root_hub;	/* Root hub */
	struct usb_bus *hs_companion;	/* Companion EHCI bus, if any */

	int bandwidth_allocated;	/* on this bus: how much of the time
					 * reserved for periodic (intr/iso)
					 * requests is used, on average?
					 * Units: microseconds/frame.
					 * Limits: Full/low speed reserve 90%,
					 * while high speed reserves 80%.
					 */
	int bandwidth_int_reqs;		/* number of Interrupt requests */
	int bandwidth_isoc_reqs;	/* number of Isoc. requests */

	unsigned resuming_ports;	/* bit array: resuming root-hub ports */

#if defined(CONFIG_USB_MON) || defined(CONFIG_USB_MON_MODULE)
	struct mon_bus *mon_bus;	/* non-null when associated */
	int monitored;			/* non-zero when monitored */
#endif
};

struct usb_dev_state;

/* ----------------------------------------------------------------------- */

struct usb_tt;

enum usb_port_connect_type {
	USB_PORT_CONNECT_TYPE_UNKNOWN = 0,
	USB_PORT_CONNECT_TYPE_HOT_PLUG,
	USB_PORT_CONNECT_TYPE_HARD_WIRED,
	USB_PORT_NOT_USED,
};

/*
 * USB port quirks.
 */

/* For the given port, prefer the old (faster) enumeration scheme. */
#define USB_PORT_QUIRK_OLD_SCHEME	BIT(0)

/* Decrease TRSTRCY to 10ms during device enumeration. */
#define USB_PORT_QUIRK_FAST_ENUM	BIT(1)

/*
 * USB 2.0 Link Power Management (LPM) parameters.
 */
struct usb2_lpm_parameters {
	/* Best effort service latency indicate how long the host will drive
	 * resume on an exit from L1.
	 */
	unsigned int besl;

	/* Timeout value in microseconds for the L1 inactivity (LPM) timer.
	 * When the timer counts to zero, the parent hub will initiate a LPM
	 * transition to L1.
	 */
	int timeout;
};

/*
 * USB 3.0 Link Power Management (LPM) parameters.
 *
 * PEL and SEL are USB 3.0 Link PM latencies for device-initiated LPM exit.
 * MEL is the USB 3.0 Link PM latency for host-initiated LPM exit.
 * All three are stored in nanoseconds.
 */
struct usb3_lpm_parameters {
	/*
	 * Maximum exit latency (MEL) for the host to send a packet to the
	 * device (either a Ping for isoc endpoints, or a data packet for
	 * interrupt endpoints), the hubs to decode the packet, and for all hubs
	 * in the path to transition the links to U0.
	 */
	unsigned int mel;
	/*
	 * Maximum exit latency for a device-initiated LPM transition to bring
	 * all links into U0.  Abbreviated as "PEL" in section 9.4.12 of the USB
	 * 3.0 spec, with no explanation of what "P" stands for.  "Path"?
	 */
	unsigned int pel;

	/*
	 * The System Exit Latency (SEL) includes PEL, and three other
	 * latencies.  After a device initiates a U0 transition, it will take
	 * some time from when the device sends the ERDY to when it will finally
	 * receive the data packet.  Basically, SEL should be the worse-case
	 * latency from when a device starts initiating a U0 transition to when
	 * it will get data.
	 */
	unsigned int sel;
	/*
	 * The idle timeout value that is currently programmed into the parent
	 * hub for this device.  When the timer counts to zero, the parent hub
	 * will initiate an LPM transition to either U1 or U2.
	 */
	int timeout;
};

/**
 * struct usb_device - kernel's representation of a USB device
 * @devnum: device number; address on a USB bus
 * @devpath: device ID string for use in messages (e.g., /port/...)
 * @route: tree topology hex string for use with xHCI
 * @state: device state: configured, not attached, etc.
 * @speed: device speed: high/full/low (or error)
 * @rx_lanes: number of rx lanes in use, USB 3.2 adds dual-lane support
 * @tx_lanes: number of tx lanes in use, USB 3.2 adds dual-lane support
 * @ssp_rate: SuperSpeed Plus phy signaling rate and lane count
 * @tt: Transaction Translator info; used with low/full speed dev, highspeed hub
 * @ttport: device port on that tt hub
 * @toggle: one bit for each endpoint, with ([0] = IN, [1] = OUT) endpoints
 * @parent: our hub, unless we're the root
 * @bus: bus we're part of
 * @ep0: endpoint 0 data (default control pipe)
 * @dev: generic device interface
 * @descriptor: USB device descriptor
 * @bos: USB device BOS descriptor set
 * @config: all of the device's configs
 * @actconfig: the active configuration
 * @ep_in: array of IN endpoints
 * @ep_out: array of OUT endpoints
 * @rawdescriptors: raw descriptors for each config
 * @bus_mA: Current available from the bus
 * @portnum: parent port number (origin 1)
 * @level: number of USB hub ancestors
 * @devaddr: device address, XHCI: assigned by HW, others: same as devnum
 * @can_submit: URBs may be submitted
 * @persist_enabled:  USB_PERSIST enabled for this device
 * @reset_in_progress: the device is being reset
 * @have_langid: whether string_langid is valid
 * @authorized: policy has said we can use it;
 *	(user space) policy determines if we authorize this device to be
 *	used or not. By default, wired USB devices are authorized.
 *	WUSB devices are not, until we authorize them from user space.
 *	FIXME -- complete doc
 * @authenticated: Crypto authentication passed
 * @wusb: device is Wireless USB
 * @lpm_capable: device supports LPM
 * @lpm_devinit_allow: Allow USB3 device initiated LPM, exit latency is in range
 * @usb2_hw_lpm_capable: device can perform USB2 hardware LPM
 * @usb2_hw_lpm_besl_capable: device can perform USB2 hardware BESL LPM
 * @usb2_hw_lpm_enabled: USB2 hardware LPM is enabled
 * @usb2_hw_lpm_allowed: Userspace allows USB 2.0 LPM to be enabled
 * @usb3_lpm_u1_enabled: USB3 hardware U1 LPM enabled
 * @usb3_lpm_u2_enabled: USB3 hardware U2 LPM enabled
 * @string_langid: language ID for strings
 * @product: iProduct string, if present (static)
 * @manufacturer: iManufacturer string, if present (static)
 * @serial: iSerialNumber string, if present (static)
 * @filelist: usbfs files that are open to this device
 * @maxchild: number of ports if hub
 * @quirks: quirks of the whole device
 * @urbnum: number of URBs submitted for the whole device
 * @active_duration: total time device is not suspended
 * @connect_time: time device was first connected
 * @do_remote_wakeup:  remote wakeup should be enabled
 * @reset_resume: needs reset instead of resume
 * @port_is_suspended: the upstream port is suspended (L2 or U3)
 * @wusb_dev: if this is a Wireless USB device, link to the WUSB
 *	specific data for the device.
 * @slot_id: Slot ID assigned by xHCI
 * @removable: Device can be physically removed from this port
 * @l1_params: best effor service latency for USB2 L1 LPM state, and L1 timeout.
 * @u1_params: exit latencies for USB3 U1 LPM state, and hub-initiated timeout.
 * @u2_params: exit latencies for USB3 U2 LPM state, and hub-initiated timeout.
 * @lpm_disable_count: Ref count used by usb_disable_lpm() and usb_enable_lpm()
 *	to keep track of the number of functions that require USB 3.0 Link Power
 *	Management to be disabled for this usb_device.  This count should only
 *	be manipulated by those functions, with the bandwidth_mutex is held.
 * @hub_delay: cached value consisting of:
 *	parent->hub_delay + wHubDelay + tTPTransmissionDelay (40ns)
 *	Will be used as wValue for SetIsochDelay requests.
 * @use_generic_driver: ask driver core to reprobe using the generic driver.
 *
 * Notes:
 * Usbcore drivers should not set usbdev->state directly.  Instead use
 * usb_set_device_state().
 */
struct usb_device {
	int		devnum;
	char		devpath[16];
	u32		route;
	enum usb_device_state	state;
	enum usb_device_speed	speed;
	unsigned int		rx_lanes;
	unsigned int		tx_lanes;
	enum usb_ssp_rate	ssp_rate;

	struct usb_tt	*tt;
	int		ttport;

	unsigned int toggle[2];

	struct usb_device *parent;
	struct usb_bus *bus;
	struct usb_host_endpoint ep0;

	struct device dev;

	struct usb_device_descriptor descriptor;
	struct usb_host_bos *bos;
	struct usb_host_config *config;

	struct usb_host_config *actconfig;
	struct usb_host_endpoint *ep_in[16];
	struct usb_host_endpoint *ep_out[16];

	char **rawdescriptors;

	unsigned short bus_mA;
	u8 portnum;
	u8 level;
	u8 devaddr;

	unsigned can_submit:1;
	unsigned persist_enabled:1;
	unsigned reset_in_progress:1;
	unsigned have_langid:1;
	unsigned authorized:1;
	unsigned authenticated:1;
	unsigned wusb:1;
	unsigned lpm_capable:1;
	unsigned lpm_devinit_allow:1;
	unsigned usb2_hw_lpm_capable:1;
	unsigned usb2_hw_lpm_besl_capable:1;
	unsigned usb2_hw_lpm_enabled:1;
	unsigned usb2_hw_lpm_allowed:1;
	unsigned usb3_lpm_u1_enabled:1;
	unsigned usb3_lpm_u2_enabled:1;
	int string_langid;

	/* static strings from the device */
	char *product;
	char *manufacturer;
	char *serial;

	struct list_head filelist;

	int maxchild;

	u32 quirks;
	atomic_t urbnum;

	unsigned long active_duration;

	unsigned long connect_time;

	unsigned do_remote_wakeup:1;
	unsigned reset_resume:1;
	unsigned port_is_suspended:1;

	struct wusb_dev *wusb_dev;
	int slot_id;
	struct usb2_lpm_parameters l1_params;
	struct usb3_lpm_parameters u1_params;
	struct usb3_lpm_parameters u2_params;
	unsigned lpm_disable_count;

	u16 hub_delay;
	unsigned use_generic_driver:1;
};

#define to_usb_device(__dev)	container_of_const(__dev, struct usb_device, dev)

static inline struct usb_device *__intf_to_usbdev(struct usb_interface *intf)
{
	return to_usb_device(intf->dev.parent);
}
static inline const struct usb_device *__intf_to_usbdev_const(const struct usb_interface *intf)
{
	return to_usb_device((const struct device *)intf->dev.parent);
}

#define interface_to_usbdev(intf)					\
	_Generic((intf),						\
		 const struct usb_interface *: __intf_to_usbdev_const,	\
		 struct usb_interface *: __intf_to_usbdev)(intf)

extern struct usb_device *usb_get_dev(struct usb_device *dev);
extern void usb_put_dev(struct usb_device *dev);
extern struct usb_device *usb_hub_find_child(struct usb_device *hdev,
	int port1);

/**
 * usb_hub_for_each_child - iterate over all child devices on the hub
 * @hdev:  USB device belonging to the usb hub
 * @port1: portnum associated with child device
 * @child: child device pointer
 */
#define usb_hub_for_each_child(hdev, port1, child) \
	for (port1 = 1,	child =	usb_hub_find_child(hdev, port1); \
			port1 <= hdev->maxchild; \
			child = usb_hub_find_child(hdev, ++port1)) \
		if (!child) continue; else

/* USB device locking */
#define usb_lock_device(udev)			device_lock(&(udev)->dev)
#define usb_unlock_device(udev)			device_unlock(&(udev)->dev)
#define usb_lock_device_interruptible(udev)	device_lock_interruptible(&(udev)->dev)
#define usb_trylock_device(udev)		device_trylock(&(udev)->dev)
extern int usb_lock_device_for_reset(struct usb_device *udev,
				     const struct usb_interface *iface);

/* USB port reset for device reinitialization */
extern int usb_reset_device(struct usb_device *dev);
extern void usb_queue_reset_device(struct usb_interface *dev);

extern struct device *usb_intf_get_dma_device(struct usb_interface *intf);

#ifdef CONFIG_ACPI
extern int usb_acpi_set_power_state(struct usb_device *hdev, int index,
	bool enable);
extern bool usb_acpi_power_manageable(struct usb_device *hdev, int index);
extern int usb_acpi_port_lpm_incapable(struct usb_device *hdev, int index);
#else
static inline int usb_acpi_set_power_state(struct usb_device *hdev, int index,
	bool enable) { return 0; }
static inline bool usb_acpi_power_manageable(struct usb_device *hdev, int index)
	{ return true; }
static inline int usb_acpi_port_lpm_incapable(struct usb_device *hdev, int index)
	{ return 0; }
#endif

/* USB autosuspend and autoresume */
#ifdef CONFIG_PM
extern void usb_enable_autosuspend(struct usb_device *udev);
extern void usb_disable_autosuspend(struct usb_device *udev);

extern int usb_autopm_get_interface(struct usb_interface *intf);
extern void usb_autopm_put_interface(struct usb_interface *intf);
extern int usb_autopm_get_interface_async(struct usb_interface *intf);
extern void usb_autopm_put_interface_async(struct usb_interface *intf);
extern void usb_autopm_get_interface_no_resume(struct usb_interface *intf);
extern void usb_autopm_put_interface_no_suspend(struct usb_interface *intf);

static inline void usb_mark_last_busy(struct usb_device *udev)
{
	pm_runtime_mark_last_busy(&udev->dev);
}

#else

static inline int usb_enable_autosuspend(struct usb_device *udev)
{ return 0; }
static inline int usb_disable_autosuspend(struct usb_device *udev)
{ return 0; }

static inline int usb_autopm_get_interface(struct usb_interface *intf)
{ return 0; }
static inline int usb_autopm_get_interface_async(struct usb_interface *intf)
{ return 0; }

static inline void usb_autopm_put_interface(struct usb_interface *intf)
{ }
static inline void usb_autopm_put_interface_async(struct usb_interface *intf)
{ }
static inline void usb_autopm_get_interface_no_resume(
		struct usb_interface *intf)
{ }
static inline void usb_autopm_put_interface_no_suspend(
		struct usb_interface *intf)
{ }
static inline void usb_mark_last_busy(struct usb_device *udev)
{ }
#endif

extern int usb_disable_lpm(struct usb_device *udev);
extern void usb_enable_lpm(struct usb_device *udev);
/* Same as above, but these functions lock/unlock the bandwidth_mutex. */
extern int usb_unlocked_disable_lpm(struct usb_device *udev);
extern void usb_unlocked_enable_lpm(struct usb_device *udev);

extern int usb_disable_ltm(struct usb_device *udev);
extern void usb_enable_ltm(struct usb_device *udev);

static inline bool usb_device_supports_ltm(struct usb_device *udev)
{
	if (udev->speed < USB_SPEED_SUPER || !udev->bos || !udev->bos->ss_cap)
		return false;
	return udev->bos->ss_cap->bmAttributes & USB_LTM_SUPPORT;
}

static inline bool usb_device_no_sg_constraint(struct usb_device *udev)
{
	return udev && udev->bus && udev->bus->no_sg_constraint;
}


/*-------------------------------------------------------------------------*/

/* for drivers using iso endpoints */
extern int usb_get_current_frame_number(struct usb_device *usb_dev);

/* Sets up a group of bulk endpoints to support multiple stream IDs. */
extern int usb_alloc_streams(struct usb_interface *interface,
		struct usb_host_endpoint **eps, unsigned int num_eps,
		unsigned int num_streams, gfp_t mem_flags);

/* Reverts a group of bulk endpoints back to not using stream IDs. */
extern int usb_free_streams(struct usb_interface *interface,
		struct usb_host_endpoint **eps, unsigned int num_eps,
		gfp_t mem_flags);

/* used these for multi-interface device registration */
extern int usb_driver_claim_interface(struct usb_driver *driver,
			struct usb_interface *iface, void *data);

/**
 * usb_interface_claimed - returns true iff an interface is claimed
 * @iface: the interface being checked
 *
 * Return: %true (nonzero) iff the interface is claimed, else %false
 * (zero).
 *
 * Note:
 * Callers must own the driver model's usb bus readlock.  So driver
 * probe() entries don't need extra locking, but other call contexts
 * may need to explicitly claim that lock.
 *
 */
static inline int usb_interface_claimed(struct usb_interface *iface)
{
	return (iface->dev.driver != NULL);
}

extern void usb_driver_release_interface(struct usb_driver *driver,
			struct usb_interface *iface);

int usb_set_wireless_status(struct usb_interface *iface,
			enum usb_wireless_status status);

const struct usb_device_id *usb_match_id(struct usb_interface *interface,
					 const struct usb_device_id *id);
extern int usb_match_one_id(struct usb_interface *interface,
			    const struct usb_device_id *id);

extern int usb_for_each_dev(void *data, int (*fn)(struct usb_device *, void *));
extern struct usb_interface *usb_find_interface(struct usb_driver *drv,
		int minor);
extern struct usb_interface *usb_ifnum_to_if(const struct usb_device *dev,
		unsigned ifnum);
extern struct usb_host_interface *usb_altnum_to_altsetting(
		const struct usb_interface *intf, unsigned int altnum);
extern struct usb_host_interface *usb_find_alt_setting(
		struct usb_host_config *config,
		unsigned int iface_num,
		unsigned int alt_num);

/* port claiming functions */
int usb_hub_claim_port(struct usb_device *hdev, unsigned port1,
		struct usb_dev_state *owner);
int usb_hub_release_port(struct usb_device *hdev, unsigned port1,
		struct usb_dev_state *owner);

/**
 * usb_make_path - returns stable device path in the usb tree
 * @dev: the device whose path is being constructed
 * @buf: where to put the string
 * @size: how big is "buf"?
 *
 * Return: Length of the string (> 0) or negative if size was too small.
 *
 * Note:
 * This identifier is intended to be "stable", reflecting physical paths in
 * hardware such as physical bus addresses for host controllers or ports on
 * USB hubs.  That makes it stay the same until systems are physically
 * reconfigured, by re-cabling a tree of USB devices or by moving USB host
 * controllers.  Adding and removing devices, including virtual root hubs
 * in host controller driver modules, does not change these path identifiers;
 * neither does rebooting or re-enumerating.  These are more useful identifiers
 * than changeable ("unstable") ones like bus numbers or device addresses.
 *
 * With a partial exception for devices connected to USB 2.0 root hubs, these
 * identifiers are also predictable.  So long as the device tree isn't changed,
 * plugging any USB device into a given hub port always gives it the same path.
 * Because of the use of "companion" controllers, devices connected to ports on
 * USB 2.0 root hubs (EHCI host controllers) will get one path ID if they are
 * high speed, and a different one if they are full or low speed.
 */
static inline int usb_make_path(struct usb_device *dev, char *buf, size_t size)
{
	int actual;
	actual = snprintf(buf, size, "usb-%s-%s", dev->bus->bus_name,
			  dev->devpath);
	return (actual >= (int)size) ? -1 : actual;
}

/*-------------------------------------------------------------------------*/

#define USB_DEVICE_ID_MATCH_DEVICE \
		(USB_DEVICE_ID_MATCH_VENDOR | USB_DEVICE_ID_MATCH_PRODUCT)
#define USB_DEVICE_ID_MATCH_DEV_RANGE \
		(USB_DEVICE_ID_MATCH_DEV_LO | USB_DEVICE_ID_MATCH_DEV_HI)
#define USB_DEVICE_ID_MATCH_DEVICE_AND_VERSION \
		(USB_DEVICE_ID_MATCH_DEVICE | USB_DEVICE_ID_MATCH_DEV_RANGE)
#define USB_DEVICE_ID_MATCH_DEV_INFO \
		(USB_DEVICE_ID_MATCH_DEV_CLASS | \
		USB_DEVICE_ID_MATCH_DEV_SUBCLASS | \
		USB_DEVICE_ID_MATCH_DEV_PROTOCOL)
#define USB_DEVICE_ID_MATCH_INT_INFO \
		(USB_DEVICE_ID_MATCH_INT_CLASS | \
		USB_DEVICE_ID_MATCH_INT_SUBCLASS | \
		USB_DEVICE_ID_MATCH_INT_PROTOCOL)

/**
 * USB_DEVICE - macro used to describe a specific usb device
 * @vend: the 16 bit USB Vendor ID
 * @prod: the 16 bit USB Product ID
 *
 * This macro is used to create a struct usb_device_id that matches a
 * specific device.
 */
#define USB_DEVICE(vend, prod) \
	.match_flags = USB_DEVICE_ID_MATCH_DEVICE, \
	.idVendor = (vend), \
	.idProduct = (prod)
/**
 * USB_DEVICE_VER - describe a specific usb device with a version range
 * @vend: the 16 bit USB Vendor ID
 * @prod: the 16 bit USB Product ID
 * @lo: the bcdDevice_lo value
 * @hi: the bcdDevice_hi value
 *
 * This macro is used to create a struct usb_device_id that matches a
 * specific device, with a version range.
 */
#define USB_DEVICE_VER(vend, prod, lo, hi) \
	.match_flags = USB_DEVICE_ID_MATCH_DEVICE_AND_VERSION, \
	.idVendor = (vend), \
	.idProduct = (prod), \
	.bcdDevice_lo = (lo), \
	.bcdDevice_hi = (hi)

/**
 * USB_DEVICE_INTERFACE_CLASS - describe a usb device with a specific interface class
 * @vend: the 16 bit USB Vendor ID
 * @prod: the 16 bit USB Product ID
 * @cl: bInterfaceClass value
 *
 * This macro is used to create a struct usb_device_id that matches a
 * specific interface class of devices.
 */
#define USB_DEVICE_INTERFACE_CLASS(vend, prod, cl) \
	.match_flags = USB_DEVICE_ID_MATCH_DEVICE | \
		       USB_DEVICE_ID_MATCH_INT_CLASS, \
	.idVendor = (vend), \
	.idProduct = (prod), \
	.bInterfaceClass = (cl)

/**
 * USB_DEVICE_INTERFACE_PROTOCOL - describe a usb device with a specific interface protocol
 * @vend: the 16 bit USB Vendor ID
 * @prod: the 16 bit USB Product ID
 * @pr: bInterfaceProtocol value
 *
 * This macro is used to create a struct usb_device_id that matches a
 * specific interface protocol of devices.
 */
#define USB_DEVICE_INTERFACE_PROTOCOL(vend, prod, pr) \
	.match_flags = USB_DEVICE_ID_MATCH_DEVICE | \
		       USB_DEVICE_ID_MATCH_INT_PROTOCOL, \
	.idVendor = (vend), \
	.idProduct = (prod), \
	.bInterfaceProtocol = (pr)

/**
 * USB_DEVICE_INTERFACE_NUMBER - describe a usb device with a specific interface number
 * @vend: the 16 bit USB Vendor ID
 * @prod: the 16 bit USB Product ID
 * @num: bInterfaceNumber value
 *
 * This macro is used to create a struct usb_device_id that matches a
 * specific interface number of devices.
 */
#define USB_DEVICE_INTERFACE_NUMBER(vend, prod, num) \
	.match_flags = USB_DEVICE_ID_MATCH_DEVICE | \
		       USB_DEVICE_ID_MATCH_INT_NUMBER, \
	.idVendor = (vend), \
	.idProduct = (prod), \
	.bInterfaceNumber = (num)

/**
 * USB_DEVICE_INFO - macro used to describe a class of usb devices
 * @cl: bDeviceClass value
 * @sc: bDeviceSubClass value
 * @pr: bDeviceProtocol value
 *
 * This macro is used to create a struct usb_device_id that matches a
 * specific class of devices.
 */
#define USB_DEVICE_INFO(cl, sc, pr) \
	.match_flags = USB_DEVICE_ID_MATCH_DEV_INFO, \
	.bDeviceClass = (cl), \
	.bDeviceSubClass = (sc), \
	.bDeviceProtocol = (pr)

/**
 * USB_INTERFACE_INFO - macro used to describe a class of usb interfaces
 * @cl: bInterfaceClass value
 * @sc: bInterfaceSubClass value
 * @pr: bInterfaceProtocol value
 *
 * This macro is used to create a struct usb_device_id that matches a
 * specific class of interfaces.
 */
#define USB_INTERFACE_INFO(cl, sc, pr) \
	.match_flags = USB_DEVICE_ID_MATCH_INT_INFO, \
	.bInterfaceClass = (cl), \
	.bInterfaceSubClass = (sc), \
	.bInterfaceProtocol = (pr)

/**
 * USB_DEVICE_AND_INTERFACE_INFO - describe a specific usb device with a class of usb interfaces
 * @vend: the 16 bit USB Vendor ID
 * @prod: the 16 bit USB Product ID
 * @cl: bInterfaceClass value
 * @sc: bInterfaceSubClass value
 * @pr: bInterfaceProtocol value
 *
 * This macro is used to create a struct usb_device_id that matches a
 * specific device with a specific class of interfaces.
 *
 * This is especially useful when explicitly matching devices that have
 * vendor specific bDeviceClass values, but standards-compliant interfaces.
 */
#define USB_DEVICE_AND_INTERFACE_INFO(vend, prod, cl, sc, pr) \
	.match_flags = USB_DEVICE_ID_MATCH_INT_INFO \
		| USB_DEVICE_ID_MATCH_DEVICE, \
	.idVendor = (vend), \
	.idProduct = (prod), \
	.bInterfaceClass = (cl), \
	.bInterfaceSubClass = (sc), \
	.bInterfaceProtocol = (pr)

/**
 * USB_VENDOR_AND_INTERFACE_INFO - describe a specific usb vendor with a class of usb interfaces
 * @vend: the 16 bit USB Vendor ID
 * @cl: bInterfaceClass value
 * @sc: bInterfaceSubClass value
 * @pr: bInterfaceProtocol value
 *
 * This macro is used to create a struct usb_device_id that matches a
 * specific vendor with a specific class of interfaces.
 *
 * This is especially useful when explicitly matching devices that have
 * vendor specific bDeviceClass values, but standards-compliant interfaces.
 */
#define USB_VENDOR_AND_INTERFACE_INFO(vend, cl, sc, pr) \
	.match_flags = USB_DEVICE_ID_MATCH_INT_INFO \
		| USB_DEVICE_ID_MATCH_VENDOR, \
	.idVendor = (vend), \
	.bInterfaceClass = (cl), \
	.bInterfaceSubClass = (sc), \
	.bInterfaceProtocol = (pr)

/* ----------------------------------------------------------------------- */

/* Stuff for dynamic usb ids */
struct usb_dynids {
	spinlock_t lock;
	struct list_head list;
};

struct usb_dynid {
	struct list_head node;
	struct usb_device_id id;
};

extern ssize_t usb_store_new_id(struct usb_dynids *dynids,
				const struct usb_device_id *id_table,
				struct device_driver *driver,
				const char *buf, size_t count);

extern ssize_t usb_show_dynids(struct usb_dynids *dynids, char *buf);

/**
 * struct usbdrv_wrap - wrapper for driver-model structure
 * @driver: The driver-model core driver structure.
 * @for_devices: Non-zero for device drivers, 0 for interface drivers.
 */
struct usbdrv_wrap {
	struct device_driver driver;
	int for_devices;
};

/**
 * struct usb_driver - identifies USB interface driver to usbcore
 * @name: The driver name should be unique among USB drivers,
 *	and should normally be the same as the module name.
 * @probe: Called to see if the driver is willing to manage a particular
 *	interface on a device.  If it is, probe returns zero and uses
 *	usb_set_intfdata() to associate driver-specific data with the
 *	interface.  It may also use usb_set_interface() to specify the
 *	appropriate altsetting.  If unwilling to manage the interface,
 *	return -ENODEV, if genuine IO errors occurred, an appropriate
 *	negative errno value.
 * @disconnect: Called when the interface is no longer accessible, usually
 *	because its device has been (or is being) disconnected or the
 *	driver module is being unloaded.
 * @unlocked_ioctl: Used for drivers that want to talk to userspace through
 *	the "usbfs" filesystem.  This lets devices provide ways to
 *	expose information to user space regardless of where they
 *	do (or don't) show up otherwise in the filesystem.
 * @suspend: Called when the device is going to be suspended by the
 *	system either from system sleep or runtime suspend context. The
 *	return value will be ignored in system sleep context, so do NOT
 *	try to continue using the device if suspend fails in this case.
 *	Instead, let the resume or reset-resume routine recover from
 *	the failure.
 * @resume: Called when the device is being resumed by the system.
 * @reset_resume: Called when the suspended device has been reset instead
 *	of being resumed.
 * @pre_reset: Called by usb_reset_device() when the device is about to be
 *	reset.  This routine must not return until the driver has no active
 *	URBs for the device, and no more URBs may be submitted until the
 *	post_reset method is called.
 * @post_reset: Called by usb_reset_device() after the device
 *	has been reset
 * @id_table: USB drivers use ID table to support hotplugging.
 *	Export this with MODULE_DEVICE_TABLE(usb,...).  This must be set
 *	or your driver's probe function will never get called.
 * @dev_groups: Attributes attached to the device that will be created once it
 *	is bound to the driver.
 * @dynids: used internally to hold the list of dynamically added device
 *	ids for this driver.
 * @drvwrap: Driver-model core structure wrapper.
 * @no_dynamic_id: if set to 1, the USB core will not allow dynamic ids to be
 *	added to this driver by preventing the sysfs file from being created.
 * @supports_autosuspend: if set to 0, the USB core will not allow autosuspend
 *	for interfaces bound to this driver.
 * @soft_unbind: if set to 1, the USB core will not kill URBs and disable
 *	endpoints before calling the driver's disconnect method.
 * @disable_hub_initiated_lpm: if set to 1, the USB core will not allow hubs
 *	to initiate lower power link state transitions when an idle timeout
 *	occurs.  Device-initiated USB 3.0 link PM will still be allowed.
 *
 * USB interface drivers must provide a name, probe() and disconnect()
 * methods, and an id_table.  Other driver fields are optional.
 *
 * The id_table is used in hotplugging.  It holds a set of descriptors,
 * and specialized data may be associated with each entry.  That table
 * is used by both user and kernel mode hotplugging support.
 *
 * The probe() and disconnect() methods are called in a context where
 * they can sleep, but they should avoid abusing the privilege.  Most
 * work to connect to a device should be done when the device is opened,
 * and undone at the last close.  The disconnect code needs to address
 * concurrency issues with respect to open() and close() methods, as
 * well as forcing all pending I/O requests to complete (by unlinking
 * them as necessary, and blocking until the unlinks complete).
 */
struct usb_driver {
	const char *name;

	int (*probe) (struct usb_interface *intf,
		      const struct usb_device_id *id);

	void (*disconnect) (struct usb_interface *intf);

	int (*unlocked_ioctl) (struct usb_interface *intf, unsigned int code,
			void *buf);

	int (*suspend) (struct usb_interface *intf, pm_message_t message);
	int (*resume) (struct usb_interface *intf);
	int (*reset_resume)(struct usb_interface *intf);

	int (*pre_reset)(struct usb_interface *intf);
	int (*post_reset)(struct usb_interface *intf);

	const struct usb_device_id *id_table;
	const struct attribute_group **dev_groups;

	struct usb_dynids dynids;
	struct usbdrv_wrap drvwrap;
	unsigned int no_dynamic_id:1;
	unsigned int supports_autosuspend:1;
	unsigned int disable_hub_initiated_lpm:1;
	unsigned int soft_unbind:1;
};
#define	to_usb_driver(d) container_of(d, struct usb_driver, drvwrap.driver)

/**
 * struct usb_device_driver - identifies USB device driver to usbcore
 * @name: The driver name should be unique among USB drivers,
 *	and should normally be the same as the module name.
 * @match: If set, used for better device/driver matching.
 * @probe: Called to see if the driver is willing to manage a particular
 *	device.  If it is, probe returns zero and uses dev_set_drvdata()
 *	to associate driver-specific data with the device.  If unwilling
 *	to manage the device, return a negative errno value.
 * @disconnect: Called when the device is no longer accessible, usually
 *	because it has been (or is being) disconnected or the driver's
 *	module is being unloaded.
 * @suspend: Called when the device is going to be suspended by the system.
 * @resume: Called when the device is being resumed by the system.
 * @dev_groups: Attributes attached to the device that will be created once it
 *	is bound to the driver.
 * @drvwrap: Driver-model core structure wrapper.
 * @id_table: used with @match() to select better matching driver at
 * 	probe() time.
 * @supports_autosuspend: if set to 0, the USB core will not allow autosuspend
 *	for devices bound to this driver.
 * @generic_subclass: if set to 1, the generic USB driver's probe, disconnect,
 *	resume and suspend functions will be called in addition to the driver's
 *	own, so this part of the setup does not need to be replicated.
 *
 * USB drivers must provide all the fields listed above except drvwrap,
 * match, and id_table.
 */
struct usb_device_driver {
	const char *name;

	bool (*match) (struct usb_device *udev);
	int (*probe) (struct usb_device *udev);
	void (*disconnect) (struct usb_device *udev);

	int (*suspend) (struct usb_device *udev, pm_message_t message);
	int (*resume) (struct usb_device *udev, pm_message_t message);
	const struct attribute_group **dev_groups;
	struct usbdrv_wrap drvwrap;
	const struct usb_device_id *id_table;
	unsigned int supports_autosuspend:1;
	unsigned int generic_subclass:1;
};
#define	to_usb_device_driver(d) container_of(d, struct usb_device_driver, \
		drvwrap.driver)

/**
 * struct usb_class_driver - identifies a USB driver that wants to use the USB major number
 * @name: the usb class device name for this driver.  Will show up in sysfs.
 * @devnode: Callback to provide a naming hint for a possible
 *	device node to create.
 * @fops: pointer to the struct file_operations of this driver.
 * @minor_base: the start of the minor range for this driver.
 *
 * This structure is used for the usb_register_dev() and
 * usb_deregister_dev() functions, to consolidate a number of the
 * parameters used for them.
 */
struct usb_class_driver {
	char *name;
	char *(*devnode)(const struct device *dev, umode_t *mode);
	const struct file_operations *fops;
	int minor_base;
};

/*
 * use these in module_init()/module_exit()
 * and don't forget MODULE_DEVICE_TABLE(usb, ...)
 */
extern int usb_register_driver(struct usb_driver *, struct module *,
			       const char *);

/* use a define to avoid include chaining to get THIS_MODULE & friends */
#define usb_register(driver) \
	usb_register_driver(driver, THIS_MODULE, KBUILD_MODNAME)

extern void usb_deregister(struct usb_driver *);

/**
 * module_usb_driver() - Helper macro for registering a USB driver
 * @__usb_driver: usb_driver struct
 *
 * Helper macro for USB drivers which do not do anything special in module
 * init/exit. This eliminates a lot of boilerplate. Each module may only
 * use this macro once, and calling it replaces module_init() and module_exit()
 */
#define module_usb_driver(__usb_driver) \
	module_driver(__usb_driver, usb_register, \
		       usb_deregister)

extern int usb_register_device_driver(struct usb_device_driver *,
			struct module *);
extern void usb_deregister_device_driver(struct usb_device_driver *);

extern int usb_register_dev(struct usb_interface *intf,
			    struct usb_class_driver *class_driver);
extern void usb_deregister_dev(struct usb_interface *intf,
			       struct usb_class_driver *class_driver);

extern int usb_disabled(void);

/* ----------------------------------------------------------------------- */

/*
 * URB support, for asynchronous request completions
 */

/*
 * urb->transfer_flags:
 *
 * Note: URB_DIR_IN/OUT is automatically set in usb_submit_urb().
 */
#define URB_SHORT_NOT_OK	0x0001	/* report short reads as errors */
#define URB_ISO_ASAP		0x0002	/* iso-only; use the first unexpired
					 * slot in the schedule */
#define URB_NO_TRANSFER_DMA_MAP	0x0004	/* urb->transfer_dma valid on submit */
#define URB_ZERO_PACKET		0x0040	/* Finish bulk OUT with short packet */
#define URB_NO_INTERRUPT	0x0080	/* HINT: no non-error interrupt
					 * needed */
#define URB_FREE_BUFFER		0x0100	/* Free transfer buffer with the URB */

/* The following flags are used internally by usbcore and HCDs */
#define URB_DIR_IN		0x0200	/* Transfer from device to host */
#define URB_DIR_OUT		0
#define URB_DIR_MASK		URB_DIR_IN

#define URB_DMA_MAP_SINGLE	0x00010000	/* Non-scatter-gather mapping */
#define URB_DMA_MAP_PAGE	0x00020000	/* HCD-unsupported S-G */
#define URB_DMA_MAP_SG		0x00040000	/* HCD-supported S-G */
#define URB_MAP_LOCAL		0x00080000	/* HCD-local-memory mapping */
#define URB_SETUP_MAP_SINGLE	0x00100000	/* Setup packet DMA mapped */
#define URB_SETUP_MAP_LOCAL	0x00200000	/* HCD-local setup packet */
#define URB_DMA_SG_COMBINED	0x00400000	/* S-G entries were combined */
#define URB_ALIGNED_TEMP_BUFFER	0x00800000	/* Temp buffer was alloc'd */

struct usb_iso_packet_descriptor {
	unsigned int offset;
	unsigned int length;		/* expected length */
	unsigned int actual_length;
	int status;
};

struct urb;

struct usb_anchor {
	struct list_head urb_list;
	wait_queue_head_t wait;
	spinlock_t lock;
	atomic_t suspend_wakeups;
	unsigned int poisoned:1;
};

static inline void init_usb_anchor(struct usb_anchor *anchor)
{
	memset(anchor, 0, sizeof(*anchor));
	INIT_LIST_HEAD(&anchor->urb_list);
	init_waitqueue_head(&anchor->wait);
	spin_lock_init(&anchor->lock);
}

typedef void (*usb_complete_t)(struct urb *);

/**
 * struct urb - USB Request Block
 * @urb_list: For use by current owner of the URB.
 * @anchor_list: membership in the list of an anchor
 * @anchor: to anchor URBs to a common mooring
 * @ep: Points to the endpoint's data structure.  Will eventually
 *	replace @pipe.
 * @pipe: Holds endpoint number, direction, type, and more.
 *	Create these values with the eight macros available;
 *	usb_{snd,rcv}TYPEpipe(dev,endpoint), where the TYPE is "ctrl"
 *	(control), "bulk", "int" (interrupt), or "iso" (isochronous).
 *	For example usb_sndbulkpipe() or usb_rcvintpipe().  Endpoint
 *	numbers range from zero to fifteen.  Note that "in" endpoint two
 *	is a different endpoint (and pipe) from "out" endpoint two.
 *	The current configuration controls the existence, type, and
 *	maximum packet size of any given endpoint.
 * @stream_id: the endpoint's stream ID for bulk streams
 * @dev: Identifies the USB device to perform the request.
 * @status: This is read in non-iso completion functions to get the
 *	status of the particular request.  ISO requests only use it
 *	to tell whether the URB was unlinked; detailed status for
 *	each frame is in the fields of the iso_frame-desc.
 * @transfer_flags: A variety of flags may be used to affect how URB
 *	submission, unlinking, or operation are handled.  Different
 *	kinds of URB can use different flags.
 * @transfer_buffer:  This identifies the buffer to (or from) which the I/O
 *	request will be performed unless URB_NO_TRANSFER_DMA_MAP is set
 *	(however, do not leave garbage in transfer_buffer even then).
 *	This buffer must be suitable for DMA; allocate it with
 *	kmalloc() or equivalent.  For transfers to "in" endpoints, contents
 *	of this buffer will be modified.  This buffer is used for the data
 *	stage of control transfers.
 * @transfer_dma: When transfer_flags includes URB_NO_TRANSFER_DMA_MAP,
 *	the device driver is saying that it provided this DMA address,
 *	which the host controller driver should use in preference to the
 *	transfer_buffer.
 * @sg: scatter gather buffer list, the buffer size of each element in
 * 	the list (except the last) must be divisible by the endpoint's
 * 	max packet size if no_sg_constraint isn't set in 'struct usb_bus'
 * @num_mapped_sgs: (internal) number of mapped sg entries
 * @num_sgs: number of entries in the sg list
 * @transfer_buffer_length: How big is transfer_buffer.  The transfer may
 *	be broken up into chunks according to the current maximum packet
 *	size for the endpoint, which is a function of the configuration
 *	and is encoded in the pipe.  When the length is zero, neither
 *	transfer_buffer nor transfer_dma is used.
 * @actual_length: This is read in non-iso completion functions, and
 *	it tells how many bytes (out of transfer_buffer_length) were
 *	transferred.  It will normally be the same as requested, unless
 *	either an error was reported or a short read was performed.
 *	The URB_SHORT_NOT_OK transfer flag may be used to make such
 *	short reads be reported as errors.
 * @setup_packet: Only used for control transfers, this points to eight bytes
 *	of setup data.  Control transfers always start by sending this data
 *	to the device.  Then transfer_buffer is read or written, if needed.
 * @setup_dma: DMA pointer for the setup packet.  The caller must not use
 *	this field; setup_packet must point to a valid buffer.
 * @start_frame: Returns the initial frame for isochronous transfers.
 * @number_of_packets: Lists the number of ISO transfer buffers.
 * @interval: Specifies the polling interval for interrupt or isochronous
 *	transfers.  The units are frames (milliseconds) for full and low
 *	speed devices, and microframes (1/8 millisecond) for highspeed
 *	and SuperSpeed devices.
 * @error_count: Returns the number of ISO transfers that reported errors.
 * @context: For use in completion functions.  This normally points to
 *	request-specific driver context.
 * @complete: Completion handler. This URB is passed as the parameter to the
 *	completion function.  The completion function may then do what
 *	it likes with the URB, including resubmitting or freeing it.
 * @iso_frame_desc: Used to provide arrays of ISO transfer buffers and to
 *	collect the transfer status for each buffer.
 *
 * This structure identifies USB transfer requests.  URBs must be allocated by
 * calling usb_alloc_urb() and freed with a call to usb_free_urb().
 * Initialization may be done using various usb_fill_*_urb() functions.  URBs
 * are submitted using usb_submit_urb(), and pending requests may be canceled
 * using usb_unlink_urb() or usb_kill_urb().
 *
 * Data Transfer Buffers:
 *
 * Normally drivers provide I/O buffers allocated with kmalloc() or otherwise
 * taken from the general page pool.  That is provided by transfer_buffer
 * (control requests also use setup_packet), and host controller drivers
 * perform a dma mapping (and unmapping) for each buffer transferred.  Those
 * mapping operations can be expensive on some platforms (perhaps using a dma
 * bounce buffer or talking to an IOMMU),
 * although they're cheap on commodity x86 and ppc hardware.
 *
 * Alternatively, drivers may pass the URB_NO_TRANSFER_DMA_MAP transfer flag,
 * which tells the host controller driver that no such mapping is needed for
 * the transfer_buffer since
 * the device driver is DMA-aware.  For example, a device driver might
 * allocate a DMA buffer with usb_alloc_coherent() or call usb_buffer_map().
 * When this transfer flag is provided, host controller drivers will
 * attempt to use the dma address found in the transfer_dma
 * field rather than determining a dma address themselves.
 *
 * Note that transfer_buffer must still be set if the controller
 * does not support DMA (as indicated by hcd_uses_dma()) and when talking
 * to root hub. If you have to transfer between highmem zone and the device
 * on such controller, create a bounce buffer or bail out with an error.
 * If transfer_buffer cannot be set (is in highmem) and the controller is DMA
 * capable, assign NULL to it, so that usbmon knows not to use the value.
 * The setup_packet must always be set, so it cannot be located in highmem.
 *
 * Initialization:
 *
 * All URBs submitted must initialize the dev, pipe, transfer_flags (may be
 * zero), and complete fields.  All URBs must also initialize
 * transfer_buffer and transfer_buffer_length.  They may provide the
 * URB_SHORT_NOT_OK transfer flag, indicating that short reads are
 * to be treated as errors; that flag is invalid for write requests.
 *
 * Bulk URBs may
 * use the URB_ZERO_PACKET transfer flag, indicating that bulk OUT transfers
 * should always terminate with a short packet, even if it means adding an
 * extra zero length packet.
 *
 * Control URBs must provide a valid pointer in the setup_packet field.
 * Unlike the transfer_buffer, the setup_packet may not be mapped for DMA
 * beforehand.
 *
 * Interrupt URBs must provide an interval, saying how often (in milliseconds
 * or, for highspeed devices, 125 microsecond units)
 * to poll for transfers.  After the URB has been submitted, the interval
 * field reflects how the transfer was actually scheduled.
 * The polling interval may be more frequent than requested.
 * For example, some controllers have a maximum interval of 32 milliseconds,
 * while others support intervals of up to 1024 milliseconds.
 * Isochronous URBs also have transfer intervals.  (Note that for isochronous
 * endpoints, as well as high speed interrupt endpoints, the encoding of
 * the transfer interval in the endpoint descriptor is logarithmic.
 * Device drivers must convert that value to linear units themselves.)
 *
 * If an isochronous endpoint queue isn't already running, the host
 * controller will schedule a new URB to start as soon as bandwidth
 * utilization allows.  If the queue is running then a new URB will be
 * scheduled to start in the first transfer slot following the end of the
 * preceding URB, if that slot has not already expired.  If the slot has
 * expired (which can happen when IRQ delivery is delayed for a long time),
 * the scheduling behavior depends on the URB_ISO_ASAP flag.  If the flag
 * is clear then the URB will be scheduled to start in the expired slot,
 * implying that some of its packets will not be transferred; if the flag
 * is set then the URB will be scheduled in the first unexpired slot,
 * breaking the queue's synchronization.  Upon URB completion, the
 * start_frame field will be set to the (micro)frame number in which the
 * transfer was scheduled.  Ranges for frame counter values are HC-specific
 * and can go from as low as 256 to as high as 65536 frames.
 *
 * Isochronous URBs have a different data transfer model, in part because
 * the quality of service is only "best effort".  Callers provide specially
 * allocated URBs, with number_of_packets worth of iso_frame_desc structures
 * at the end.  Each such packet is an individual ISO transfer.  Isochronous
 * URBs are normally queued, submitted by drivers to arrange that
 * transfers are at least double buffered, and then explicitly resubmitted
 * in completion handlers, so
 * that data (such as audio or video) streams at as constant a rate as the
 * host controller scheduler can support.
 *
 * Completion Callbacks:
 *
 * The completion callback is made in_interrupt(), and one of the first
 * things that a completion handler should do is check the status field.
 * The status field is provided for all URBs.  It is used to report
 * unlinked URBs, and status for all non-ISO transfers.  It should not
 * be examined before the URB is returned to the completion handler.
 *
 * The context field is normally used to link URBs back to the relevant
 * driver or request state.
 *
 * When the completion callback is invoked for non-isochronous URBs, the
 * actual_length field tells how many bytes were transferred.  This field
 * is updated even when the URB terminated with an error or was unlinked.
 *
 * ISO transfer status is reported in the status and actual_length fields
 * of the iso_frame_desc array, and the number of errors is reported in
 * error_count.  Completion callbacks for ISO transfers will normally
 * (re)submit URBs to ensure a constant transfer rate.
 *
 * Note that even fields marked "public" should not be touched by the driver
 * when the urb is owned by the hcd, that is, since the call to
 * usb_submit_urb() till the entry into the completion routine.
 */
struct urb {
	/* private: usb core and host controller only fields in the urb */
	struct kref kref;		/* reference count of the URB */
	int unlinked;			/* unlink error code */
	void *hcpriv;			/* private data for host controller */
	atomic_t use_count;		/* concurrent submissions counter */
	atomic_t reject;		/* submissions will fail */

	/* public: documented fields in the urb that can be used by drivers */
	struct list_head urb_list;	/* list head for use by the urb's
					 * current owner */
	struct list_head anchor_list;	/* the URB may be anchored */
	struct usb_anchor *anchor;
	struct usb_device *dev;		/* (in) pointer to associated device */
	struct usb_host_endpoint *ep;	/* (internal) pointer to endpoint */
	unsigned int pipe;		/* (in) pipe information */
	unsigned int stream_id;		/* (in) stream ID */
	int status;			/* (return) non-ISO status */
	unsigned int transfer_flags;	/* (in) URB_SHORT_NOT_OK | ...*/
	void *transfer_buffer;		/* (in) associated data buffer */
	dma_addr_t transfer_dma;	/* (in) dma addr for transfer_buffer */
	struct scatterlist *sg;		/* (in) scatter gather buffer list */
	int num_mapped_sgs;		/* (internal) mapped sg entries */
	int num_sgs;			/* (in) number of entries in the sg list */
	u32 transfer_buffer_length;	/* (in) data buffer length */
	u32 actual_length;		/* (return) actual transfer length */
	unsigned char *setup_packet;	/* (in) setup packet (control only) */
	dma_addr_t setup_dma;		/* (in) dma addr for setup_packet */
	int start_frame;		/* (modify) start frame (ISO) */
	int number_of_packets;		/* (in) number of ISO packets */
	int interval;			/* (modify) transfer interval
					 * (INT/ISO) */
	int error_count;		/* (return) number of ISO errors */
	void *context;			/* (in) context for completion */
	usb_complete_t complete;	/* (in) completion routine */
	struct usb_iso_packet_descriptor iso_frame_desc[];
					/* (in) ISO ONLY */
};

/* ----------------------------------------------------------------------- */

/**
 * usb_fill_control_urb - initializes a control urb
 * @urb: pointer to the urb to initialize.
 * @dev: pointer to the struct usb_device for this urb.
 * @pipe: the endpoint pipe
 * @setup_packet: pointer to the setup_packet buffer. The buffer must be
 *	suitable for DMA.
 * @transfer_buffer: pointer to the transfer buffer. The buffer must be
 *	suitable for DMA.
 * @buffer_length: length of the transfer buffer
 * @complete_fn: pointer to the usb_complete_t function
 * @context: what to set the urb context to.
 *
 * Initializes a control urb with the proper information needed to submit
 * it to a device.
 *
 * The transfer buffer and the setup_packet buffer will most likely be filled
 * or read via DMA. The simplest way to get a buffer that can be DMAed to is
 * allocating it via kmalloc() or equivalent, even for very small buffers.
 * If the buffers are embedded in a bigger structure, there is a risk that
 * the buffer itself, the previous fields and/or the next fields are corrupted
 * due to cache incoherencies; or slowed down if they are evicted from the
 * cache. For more information, check &struct urb.
 *
 */
static inline void usb_fill_control_urb(struct urb *urb,
					struct usb_device *dev,
					unsigned int pipe,
					unsigned char *setup_packet,
					void *transfer_buffer,
					int buffer_length,
					usb_complete_t complete_fn,
					void *context)
{
	urb->dev = dev;
	urb->pipe = pipe;
	urb->setup_packet = setup_packet;
	urb->transfer_buffer = transfer_buffer;
	urb->transfer_buffer_length = buffer_length;
	urb->complete = complete_fn;
	urb->context = context;
}

/**
 * usb_fill_bulk_urb - macro to help initialize a bulk urb
 * @urb: pointer to the urb to initialize.
 * @dev: pointer to the struct usb_device for this urb.
 * @pipe: the endpoint pipe
 * @transfer_buffer: pointer to the transfer buffer. The buffer must be
 *	suitable for DMA.
 * @buffer_length: length of the transfer buffer
 * @complete_fn: pointer to the usb_complete_t function
 * @context: what to set the urb context to.
 *
 * Initializes a bulk urb with the proper information needed to submit it
 * to a device.
 *
 * Refer to usb_fill_control_urb() for a description of the requirements for
 * transfer_buffer.
 */
static inline void usb_fill_bulk_urb(struct urb *urb,
				     struct usb_device *dev,
				     unsigned int pipe,
				     void *transfer_buffer,
				     int buffer_length,
				     usb_complete_t complete_fn,
				     void *context)
{
	urb->dev = dev;
	urb->pipe = pipe;
	urb->transfer_buffer = transfer_buffer;
	urb->transfer_buffer_length = buffer_length;
	urb->complete = complete_fn;
	urb->context = context;
}

/**
 * usb_fill_int_urb - macro to help initialize a interrupt urb
 * @urb: pointer to the urb to initialize.
 * @dev: pointer to the struct usb_device for this urb.
 * @pipe: the endpoint pipe
 * @transfer_buffer: pointer to the transfer buffer. The buffer must be
 *	suitable for DMA.
 * @buffer_length: length of the transfer buffer
 * @complete_fn: pointer to the usb_complete_t function
 * @context: what to set the urb context to.
 * @interval: what to set the urb interval to, encoded like
 *	the endpoint descriptor's bInterval value.
 *
 * Initializes a interrupt urb with the proper information needed to submit
 * it to a device.
 *
 * Refer to usb_fill_control_urb() for a description of the requirements for
 * transfer_buffer.
 *
 * Note that High Speed and SuperSpeed(+) interrupt endpoints use a logarithmic
 * encoding of the endpoint interval, and express polling intervals in
 * microframes (eight per millisecond) rather than in frames (one per
 * millisecond).
 *
 * Wireless USB also uses the logarithmic encoding, but specifies it in units of
 * 128us instead of 125us.  For Wireless USB devices, the interval is passed
 * through to the host controller, rather than being translated into microframe
 * units.
 */
static inline void usb_fill_int_urb(struct urb *urb,
				    struct usb_device *dev,
				    unsigned int pipe,
				    void *transfer_buffer,
				    int buffer_length,
				    usb_complete_t complete_fn,
				    void *context,
				    int interval)
{
	urb->dev = dev;
	urb->pipe = pipe;
	urb->transfer_buffer = transfer_buffer;
	urb->transfer_buffer_length = buffer_length;
	urb->complete = complete_fn;
	urb->context = context;

	if (dev->speed == USB_SPEED_HIGH || dev->speed >= USB_SPEED_SUPER) {
		/* make sure interval is within allowed range */
		interval = clamp(interval, 1, 16);

		urb->interval = 1 << (interval - 1);
	} else {
		urb->interval = interval;
	}

	urb->start_frame = -1;
}

extern void usb_init_urb(struct urb *urb);
extern struct urb *usb_alloc_urb(int iso_packets, gfp_t mem_flags);
extern void usb_free_urb(struct urb *urb);
#define usb_put_urb usb_free_urb
extern struct urb *usb_get_urb(struct urb *urb);
extern int usb_submit_urb(struct urb *urb, gfp_t mem_flags);
extern int usb_unlink_urb(struct urb *urb);
extern void usb_kill_urb(struct urb *urb);
extern void usb_poison_urb(struct urb *urb);
extern void usb_unpoison_urb(struct urb *urb);
extern void usb_block_urb(struct urb *urb);
extern void usb_kill_anchored_urbs(struct usb_anchor *anchor);
extern void usb_poison_anchored_urbs(struct usb_anchor *anchor);
extern void usb_unpoison_anchored_urbs(struct usb_anchor *anchor);
extern void usb_unlink_anchored_urbs(struct usb_anchor *anchor);
extern void usb_anchor_suspend_wakeups(struct usb_anchor *anchor);
extern void usb_anchor_resume_wakeups(struct usb_anchor *anchor);
extern void usb_anchor_urb(struct urb *urb, struct usb_anchor *anchor);
extern void usb_unanchor_urb(struct urb *urb);
extern int usb_wait_anchor_empty_timeout(struct usb_anchor *anchor,
					 unsigned int timeout);
extern struct urb *usb_get_from_anchor(struct usb_anchor *anchor);
extern void usb_scuttle_anchored_urbs(struct usb_anchor *anchor);
extern int usb_anchor_empty(struct usb_anchor *anchor);

#define usb_unblock_urb	usb_unpoison_urb

/**
 * usb_urb_dir_in - check if an URB describes an IN transfer
 * @urb: URB to be checked
 *
 * Return: 1 if @urb describes an IN transfer (device-to-host),
 * otherwise 0.
 */
static inline int usb_urb_dir_in(struct urb *urb)
{
	return (urb->transfer_flags & URB_DIR_MASK) == URB_DIR_IN;
}

/**
 * usb_urb_dir_out - check if an URB describes an OUT transfer
 * @urb: URB to be checked
 *
 * Return: 1 if @urb describes an OUT transfer (host-to-device),
 * otherwise 0.
 */
static inline int usb_urb_dir_out(struct urb *urb)
{
	return (urb->transfer_flags & URB_DIR_MASK) == URB_DIR_OUT;
}

int usb_pipe_type_check(struct usb_device *dev, unsigned int pipe);
int usb_urb_ep_type_check(const struct urb *urb);

void *usb_alloc_coherent(struct usb_device *dev, size_t size,
	gfp_t mem_flags, dma_addr_t *dma);
void usb_free_coherent(struct usb_device *dev, size_t size,
	void *addr, dma_addr_t dma);

#if 0
struct urb *usb_buffer_map(struct urb *urb);
void usb_buffer_dmasync(struct urb *urb);
void usb_buffer_unmap(struct urb *urb);
#endif

struct scatterlist;
int usb_buffer_map_sg(const struct usb_device *dev, int is_in,
		      struct scatterlist *sg, int nents);
#if 0
void usb_buffer_dmasync_sg(const struct usb_device *dev, int is_in,
			   struct scatterlist *sg, int n_hw_ents);
#endif
void usb_buffer_unmap_sg(const struct usb_device *dev, int is_in,
			 struct scatterlist *sg, int n_hw_ents);

/*-------------------------------------------------------------------*
 *                         SYNCHRONOUS CALL SUPPORT                  *
 *-------------------------------------------------------------------*/

extern int usb_control_msg(struct usb_device *dev, unsigned int pipe,
	__u8 request, __u8 requesttype, __u16 value, __u16 index,
	void *data, __u16 size, int timeout);
extern int usb_interrupt_msg(struct usb_device *usb_dev, unsigned int pipe,
	void *data, int len, int *actual_length, int timeout);
extern int usb_bulk_msg(struct usb_device *usb_dev, unsigned int pipe,
	void *data, int len, int *actual_length,
	int timeout);

/* wrappers around usb_control_msg() for the most common standard requests */
int usb_control_msg_send(struct usb_device *dev, __u8 endpoint, __u8 request,
			 __u8 requesttype, __u16 value, __u16 index,
			 const void *data, __u16 size, int timeout,
			 gfp_t memflags);
int usb_control_msg_recv(struct usb_device *dev, __u8 endpoint, __u8 request,
			 __u8 requesttype, __u16 value, __u16 index,
			 void *data, __u16 size, int timeout,
			 gfp_t memflags);
extern int usb_get_descriptor(struct usb_device *dev, unsigned char desctype,
	unsigned char descindex, void *buf, int size);
extern int usb_get_status(struct usb_device *dev,
	int recip, int type, int target, void *data);

static inline int usb_get_std_status(struct usb_device *dev,
	int recip, int target, void *data)
{
	return usb_get_status(dev, recip, USB_STATUS_TYPE_STANDARD, target,
		data);
}

static inline int usb_get_ptm_status(struct usb_device *dev, void *data)
{
	return usb_get_status(dev, USB_RECIP_DEVICE, USB_STATUS_TYPE_PTM,
		0, data);
}

extern int usb_string(struct usb_device *dev, int index,
	char *buf, size_t size);
extern char *usb_cache_string(struct usb_device *udev, int index);

/* wrappers that also update important state inside usbcore */
extern int usb_clear_halt(struct usb_device *dev, int pipe);
extern int usb_reset_configuration(struct usb_device *dev);
extern int usb_set_interface(struct usb_device *dev, int ifnum, int alternate);
extern void usb_reset_endpoint(struct usb_device *dev, unsigned int epaddr);

/* this request isn't really synchronous, but it belongs with the others */
extern int usb_driver_set_configuration(struct usb_device *udev, int config);

/* choose and set configuration for device */
extern int usb_choose_configuration(struct usb_device *udev);
extern int usb_set_configuration(struct usb_device *dev, int configuration);

/*
 * timeouts, in milliseconds, used for sending/receiving control messages
 * they typically complete within a few frames (msec) after they're issued
 * USB identifies 5 second timeouts, maybe more in a few cases, and a few
 * slow devices (like some MGE Ellipse UPSes) actually push that limit.
 */
#define USB_CTRL_GET_TIMEOUT	5000
#define USB_CTRL_SET_TIMEOUT	5000


/**
 * struct usb_sg_request - support for scatter/gather I/O
 * @status: zero indicates success, else negative errno
 * @bytes: counts bytes transferred.
 *
 * These requests are initialized using usb_sg_init(), and then are used
 * as request handles passed to usb_sg_wait() or usb_sg_cancel().  Most
 * members of the request object aren't for driver access.
 *
 * The status and bytecount values are valid only after usb_sg_wait()
 * returns.  If the status is zero, then the bytecount matches the total
 * from the request.
 *
 * After an error completion, drivers may need to clear a halt condition
 * on the endpoint.
 */
struct usb_sg_request {
	int			status;
	size_t			bytes;

	/* private:
	 * members below are private to usbcore,
	 * and are not provided for driver access!
	 */
	spinlock_t		lock;

	struct usb_device	*dev;
	int			pipe;

	int			entries;
	struct urb		**urbs;

	int			count;
	struct completion	complete;
};

int usb_sg_init(
	struct usb_sg_request	*io,
	struct usb_device	*dev,
	unsigned		pipe,
	unsigned		period,
	struct scatterlist	*sg,
	int			nents,
	size_t			length,
	gfp_t			mem_flags
);
void usb_sg_cancel(struct usb_sg_request *io);
void usb_sg_wait(struct usb_sg_request *io);


/* ----------------------------------------------------------------------- */

/*
 * For various legacy reasons, Linux has a small cookie that's paired with
 * a struct usb_device to identify an endpoint queue.  Queue characteristics
 * are defined by the endpoint's descriptor.  This cookie is called a "pipe",
 * an unsigned int encoded as:
 *
 *  - direction:	bit 7		(0 = Host-to-Device [Out],
 *					 1 = Device-to-Host [In] ...
 *					like endpoint bEndpointAddress)
 *  - device address:	bits 8-14       ... bit positions known to uhci-hcd
 *  - endpoint:		bits 15-18      ... bit positions known to uhci-hcd
 *  - pipe type:	bits 30-31	(00 = isochronous, 01 = interrupt,
 *					 10 = control, 11 = bulk)
 *
 * Given the device address and endpoint descriptor, pipes are redundant.
 */

/* NOTE:  these are not the standard USB_ENDPOINT_XFER_* values!! */
/* (yet ... they're the values used by usbfs) */
#define PIPE_ISOCHRONOUS		0
#define PIPE_INTERRUPT			1
#define PIPE_CONTROL			2
#define PIPE_BULK			3

#define usb_pipein(pipe)	((pipe) & USB_DIR_IN)
#define usb_pipeout(pipe)	(!usb_pipein(pipe))

#define usb_pipedevice(pipe)	(((pipe) >> 8) & 0x7f)
#define usb_pipeendpoint(pipe)	(((pipe) >> 15) & 0xf)

#define usb_pipetype(pipe)	(((pipe) >> 30) & 3)
#define usb_pipeisoc(pipe)	(usb_pipetype((pipe)) == PIPE_ISOCHRONOUS)
#define usb_pipeint(pipe)	(usb_pipetype((pipe)) == PIPE_INTERRUPT)
#define usb_pipecontrol(pipe)	(usb_pipetype((pipe)) == PIPE_CONTROL)
#define usb_pipebulk(pipe)	(usb_pipetype((pipe)) == PIPE_BULK)

static inline unsigned int __create_pipe(struct usb_device *dev,
		unsigned int endpoint)
{
	return (dev->devnum << 8) | (endpoint << 15);
}

/* Create various pipes... */
#define usb_sndctrlpipe(dev, endpoint)	\
	((PIPE_CONTROL << 30) | __create_pipe(dev, endpoint))
#define usb_rcvctrlpipe(dev, endpoint)	\
	((PIPE_CONTROL << 30) | __create_pipe(dev, endpoint) | USB_DIR_IN)
#define usb_sndisocpipe(dev, endpoint)	\
	((PIPE_ISOCHRONOUS << 30) | __create_pipe(dev, endpoint))
#define usb_rcvisocpipe(dev, endpoint)	\
	((PIPE_ISOCHRONOUS << 30) | __create_pipe(dev, endpoint) | USB_DIR_IN)
#define usb_sndbulkpipe(dev, endpoint)	\
	((PIPE_BULK << 30) | __create_pipe(dev, endpoint))
#define usb_rcvbulkpipe(dev, endpoint)	\
	((PIPE_BULK << 30) | __create_pipe(dev, endpoint) | USB_DIR_IN)
#define usb_sndintpipe(dev, endpoint)	\
	((PIPE_INTERRUPT << 30) | __create_pipe(dev, endpoint))
#define usb_rcvintpipe(dev, endpoint)	\
	((PIPE_INTERRUPT << 30) | __create_pipe(dev, endpoint) | USB_DIR_IN)

static inline struct usb_host_endpoint *
usb_pipe_endpoint(struct usb_device *dev, unsigned int pipe)
{
	struct usb_host_endpoint **eps;
	eps = usb_pipein(pipe) ? dev->ep_in : dev->ep_out;
	return eps[usb_pipeendpoint(pipe)];
}

static inline u16 usb_maxpacket(struct usb_device *udev, int pipe)
{
	struct usb_host_endpoint *ep = usb_pipe_endpoint(udev, pipe);

	if (!ep)
		return 0;

	/* NOTE:  only 0x07ff bits are for packet size... */
	return usb_endpoint_maxp(&ep->desc);
}

/* translate USB error codes to codes user space understands */
static inline int usb_translate_errors(int error_code)
{
	switch (error_code) {
	case 0:
	case -ENOMEM:
	case -ENODEV:
	case -EOPNOTSUPP:
		return error_code;
	default:
		return -EIO;
	}
}

/* Events from the usb core */
#define USB_DEVICE_ADD		0x0001
#define USB_DEVICE_REMOVE	0x0002
#define USB_BUS_ADD		0x0003
#define USB_BUS_REMOVE		0x0004
extern void usb_register_notify(struct notifier_block *nb);
extern void usb_unregister_notify(struct notifier_block *nb);

/* debugfs stuff */
extern struct dentry *usb_debug_root;

/* LED triggers */
enum usb_led_event {
	USB_LED_EVENT_HOST = 0,
	USB_LED_EVENT_GADGET = 1,
};

#ifdef CONFIG_USB_LED_TRIG
extern void usb_led_activity(enum usb_led_event ev);
#else
static inline void usb_led_activity(enum usb_led_event ev) {}
#endif

#endif  /* __KERNEL__ */

#endif