summaryrefslogtreecommitdiff
path: root/drivers/staging/ozwpan/ozhcd.c
blob: d9c43c3282e7bd7dbc94459d5f966dae9ed1d0c8 (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
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
/* -----------------------------------------------------------------------------
 * Copyright (c) 2011 Ozmo Inc
 * Released under the GNU General Public License Version 2 (GPLv2).
 *
 * This file provides the implementation of a USB host controller device that
 * does not have any associated hardware. Instead the virtual device is
 * connected to the WiFi network and emulates the operation of a USB hcd by
 * receiving and sending network frames.
 * Note:
 * We take great pains to reduce the amount of code where interrupts need to be
 * disabled and in this respect we are different from standard HCD's. In
 * particular we don't want in_irq() code bleeding over to the protocol side of
 * the driver.
 * The troublesome functions are the urb enqueue and dequeue functions both of
 * which can be called in_irq(). So for these functions we put the urbs into a
 * queue and request a tasklet to process them. This means that a spinlock with
 * interrupts disabled must be held for insertion and removal but most code is
 * is in tasklet or soft irq context. The lock that protects this list is called
 * the tasklet lock and serves the purpose of the 'HCD lock' which must be held
 * when calling the following functions.
 *   usb_hcd_link_urb_to_ep()
 *   usb_hcd_unlink_urb_from_ep()
 *   usb_hcd_flush_endpoint()
 *   usb_hcd_check_unlink_urb()
 * -----------------------------------------------------------------------------
 */
#include <linux/platform_device.h>
#include <linux/usb.h>
#include <linux/slab.h>
#include <linux/export.h>
#include "linux/usb/hcd.h"
#include <asm/unaligned.h>
#include "ozdbg.h"
#include "ozusbif.h"
#include "ozurbparanoia.h"
#include "ozhcd.h"

/*
 * Number of units of buffering to capture for an isochronous IN endpoint before
 * allowing data to be indicated up.
 */
#define OZ_IN_BUFFERING_UNITS	100

/* Name of our platform device.
 */
#define OZ_PLAT_DEV_NAME	"ozwpan"

/* Maximum number of free urb links that can be kept in the pool.
 */
#define OZ_MAX_LINK_POOL_SIZE	16

/* Get endpoint object from the containing link.
 */
#define ep_from_link(__e) container_of((__e), struct oz_endpoint, link)

/*EP0 timeout before ep0 request is again added to TX queue. (13*8 = 98mSec)
 */
#define EP0_TIMEOUT_COUNTER 13

/* Debounce time HCD driver should wait before unregistering.
 */
#define OZ_HUB_DEBOUNCE_TIMEOUT 1500

/*
 * Used to link urbs together and also store some status information for each
 * urb.
 * A cache of these are kept in a pool to reduce number of calls to kmalloc.
 */
struct oz_urb_link {
	struct list_head link;
	struct urb *urb;
	struct oz_port *port;
	u8 req_id;
	u8 ep_num;
	unsigned submit_counter;
};

/* Holds state information about a USB endpoint.
 */
#define OZ_EP_BUFFER_SIZE_ISOC  (1024 * 24)
#define OZ_EP_BUFFER_SIZE_INT   512
struct oz_endpoint {
	struct list_head urb_list;	/* List of oz_urb_link items. */
	struct list_head link;		/* For isoc ep, links in to isoc
					   lists of oz_port. */
	struct timespec timestamp;
	int credit;
	int credit_ceiling;
	u8 ep_num;
	u8 attrib;
	u8 *buffer;
	int buffer_size;
	int in_ix;
	int out_ix;
	int buffered_units;
	unsigned flags;
	int start_frame;
};

/* Bits in the flags field. */
#define OZ_F_EP_BUFFERING	0x1
#define OZ_F_EP_HAVE_STREAM	0x2

/* Holds state information about a USB interface.
 */
struct oz_interface {
	unsigned ep_mask;
	u8 alt;
};

/* Holds state information about an hcd port.
 */
#define OZ_NB_ENDPOINTS	16
struct oz_port {
	unsigned flags;
	unsigned status;
	void *hpd;
	struct oz_hcd *ozhcd;
	spinlock_t port_lock;
	u8 bus_addr;
	u8 next_req_id;
	u8 config_num;
	int num_iface;
	struct oz_interface *iface;
	struct oz_endpoint *out_ep[OZ_NB_ENDPOINTS];
	struct oz_endpoint *in_ep[OZ_NB_ENDPOINTS];
	struct list_head isoc_out_ep;
	struct list_head isoc_in_ep;
};

#define OZ_PORT_F_PRESENT	0x1
#define OZ_PORT_F_CHANGED	0x2
#define OZ_PORT_F_DYING		0x4

/* Data structure in the private context area of struct usb_hcd.
 */
#define OZ_NB_PORTS	8
struct oz_hcd {
	spinlock_t hcd_lock;
	struct list_head urb_pending_list;
	struct list_head urb_cancel_list;
	struct list_head orphanage;
	int conn_port; /* Port that is currently connecting, -1 if none.*/
	struct oz_port ports[OZ_NB_PORTS];
	uint flags;
	struct usb_hcd *hcd;
};

/* Bits in flags field.
 */
#define OZ_HDC_F_SUSPENDED	0x1

/*
 * Static function prototypes.
 */
static int oz_hcd_start(struct usb_hcd *hcd);
static void oz_hcd_stop(struct usb_hcd *hcd);
static void oz_hcd_shutdown(struct usb_hcd *hcd);
static int oz_hcd_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
				gfp_t mem_flags);
static int oz_hcd_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status);
static void oz_hcd_endpoint_disable(struct usb_hcd *hcd,
				struct usb_host_endpoint *ep);
static void oz_hcd_endpoint_reset(struct usb_hcd *hcd,
				struct usb_host_endpoint *ep);
static int oz_hcd_get_frame_number(struct usb_hcd *hcd);
static int oz_hcd_hub_status_data(struct usb_hcd *hcd, char *buf);
static int oz_hcd_hub_control(struct usb_hcd *hcd, u16 req_type, u16 wvalue,
				u16 windex, char *buf, u16 wlength);
static int oz_hcd_bus_suspend(struct usb_hcd *hcd);
static int oz_hcd_bus_resume(struct usb_hcd *hcd);
static int oz_plat_probe(struct platform_device *dev);
static int oz_plat_remove(struct platform_device *dev);
static void oz_plat_shutdown(struct platform_device *dev);
static int oz_plat_suspend(struct platform_device *dev, pm_message_t msg);
static int oz_plat_resume(struct platform_device *dev);
static void oz_urb_process_tasklet(unsigned long unused);
static int oz_build_endpoints_for_config(struct usb_hcd *hcd,
		struct oz_port *port, struct usb_host_config *config,
		gfp_t mem_flags);
static void oz_clean_endpoints_for_config(struct usb_hcd *hcd,
				struct oz_port *port);
static int oz_build_endpoints_for_interface(struct usb_hcd *hcd,
			struct oz_port *port,
			struct usb_host_interface *intf, gfp_t mem_flags);
static void oz_clean_endpoints_for_interface(struct usb_hcd *hcd,
			struct oz_port *port, int if_ix);
static void oz_process_ep0_urb(struct oz_hcd *ozhcd, struct urb *urb,
		gfp_t mem_flags);
static struct oz_urb_link *oz_remove_urb(struct oz_endpoint *ep,
		struct urb *urb);
static void oz_hcd_clear_orphanage(struct oz_hcd *ozhcd, int status);

/*
 * Static external variables.
 */
static struct platform_device *g_plat_dev;
static struct oz_hcd *g_ozhcd;
static DEFINE_SPINLOCK(g_hcdlock);	/* Guards g_ozhcd. */
static const char g_hcd_name[] = "Ozmo WPAN";
static struct list_head *g_link_pool;
static int g_link_pool_size;
static DEFINE_SPINLOCK(g_link_lock);
static DEFINE_SPINLOCK(g_tasklet_lock);
static struct tasklet_struct g_urb_process_tasklet;
static struct tasklet_struct g_urb_cancel_tasklet;
static atomic_t g_pending_urbs = ATOMIC_INIT(0);
static atomic_t g_usb_frame_number = ATOMIC_INIT(0);
static const struct hc_driver g_oz_hc_drv = {
	.description =		g_hcd_name,
	.product_desc =		"Ozmo Devices WPAN",
	.hcd_priv_size =	sizeof(struct oz_hcd),
	.flags =		HCD_USB11,
	.start =		oz_hcd_start,
	.stop =			oz_hcd_stop,
	.shutdown =		oz_hcd_shutdown,
	.urb_enqueue =		oz_hcd_urb_enqueue,
	.urb_dequeue =		oz_hcd_urb_dequeue,
	.endpoint_disable =	oz_hcd_endpoint_disable,
	.endpoint_reset =	oz_hcd_endpoint_reset,
	.get_frame_number =	oz_hcd_get_frame_number,
	.hub_status_data =	oz_hcd_hub_status_data,
	.hub_control =		oz_hcd_hub_control,
	.bus_suspend =		oz_hcd_bus_suspend,
	.bus_resume =		oz_hcd_bus_resume,
};

static struct platform_driver g_oz_plat_drv = {
	.probe = oz_plat_probe,
	.remove = oz_plat_remove,
	.shutdown = oz_plat_shutdown,
	.suspend = oz_plat_suspend,
	.resume = oz_plat_resume,
	.driver = {
		.name = OZ_PLAT_DEV_NAME,
		.owner = THIS_MODULE,
	},
};

/*
 * Gets our private context area (which is of type struct oz_hcd) from the
 * usb_hcd structure.
 * Context: any
 */
static inline struct oz_hcd *oz_hcd_private(struct usb_hcd *hcd)
{
	return (struct oz_hcd *)hcd->hcd_priv;
}

/*
 * Searches list of ports to find the index of the one with a specified  USB
 * bus address. If none of the ports has the bus address then the connection
 * port is returned, if there is one or -1 otherwise.
 * Context: any
 */
static int oz_get_port_from_addr(struct oz_hcd *ozhcd, u8 bus_addr)
{
	int i;

	for (i = 0; i < OZ_NB_PORTS; i++) {
		if (ozhcd->ports[i].bus_addr == bus_addr)
			return i;
	}
	return ozhcd->conn_port;
}

/*
 * Allocates an urb link, first trying the pool but going to heap if empty.
 * Context: any
 */
static struct oz_urb_link *oz_alloc_urb_link(void)
{
	struct oz_urb_link *urbl = NULL;
	unsigned long irq_state;

	spin_lock_irqsave(&g_link_lock, irq_state);
	if (g_link_pool) {
		urbl = container_of(g_link_pool, struct oz_urb_link, link);
		g_link_pool = urbl->link.next;
		--g_link_pool_size;
	}
	spin_unlock_irqrestore(&g_link_lock, irq_state);
	if (urbl == NULL)
		urbl = kmalloc(sizeof(struct oz_urb_link), GFP_ATOMIC);
	return urbl;
}

/*
 * Frees an urb link by putting it in the pool if there is enough space or
 * deallocating it to heap otherwise.
 * Context: any
 */
static void oz_free_urb_link(struct oz_urb_link *urbl)
{
	if (urbl) {
		unsigned long irq_state;
		spin_lock_irqsave(&g_link_lock, irq_state);
		if (g_link_pool_size < OZ_MAX_LINK_POOL_SIZE) {
			urbl->link.next = g_link_pool;
			g_link_pool = &urbl->link;
			urbl = NULL;
			g_link_pool_size++;
		}
		spin_unlock_irqrestore(&g_link_lock, irq_state);
		kfree(urbl);
	}
}

/*
 * Deallocates all the urb links in the pool.
 * Context: unknown
 */
static void oz_empty_link_pool(void)
{
	struct list_head *e;
	unsigned long irq_state;

	spin_lock_irqsave(&g_link_lock, irq_state);
	e = g_link_pool;
	g_link_pool = NULL;
	g_link_pool_size = 0;
	spin_unlock_irqrestore(&g_link_lock, irq_state);
	while (e) {
		struct oz_urb_link *urbl =
			container_of(e, struct oz_urb_link, link);
		e = e->next;
		kfree(urbl);
	}
}

/*
 * Allocates endpoint structure and optionally a buffer. If a buffer is
 * allocated it immediately follows the endpoint structure.
 * Context: softirq
 */
static struct oz_endpoint *oz_ep_alloc(int buffer_size, gfp_t mem_flags)
{
	struct oz_endpoint *ep =
		kzalloc(sizeof(struct oz_endpoint)+buffer_size, mem_flags);
	if (ep) {
		INIT_LIST_HEAD(&ep->urb_list);
		INIT_LIST_HEAD(&ep->link);
		ep->credit = -1;
		if (buffer_size) {
			ep->buffer_size = buffer_size;
			ep->buffer = (u8 *)(ep+1);
		}
	}
	return ep;
}

/*
 * Pre-condition: Must be called with g_tasklet_lock held and interrupts
 * disabled.
 * Context: softirq or process
 */
static struct oz_urb_link *oz_uncancel_urb(struct oz_hcd *ozhcd, struct urb *urb)
{
	struct oz_urb_link *urbl;
	struct list_head *e;

	list_for_each(e, &ozhcd->urb_cancel_list) {
		urbl = container_of(e, struct oz_urb_link, link);
		if (urb == urbl->urb) {
			list_del_init(e);
			return urbl;
		}
	}
	return NULL;
}

/*
 * This is called when we have finished processing an urb. It unlinks it from
 * the ep and returns it to the core.
 * Context: softirq or process
 */
static void oz_complete_urb(struct usb_hcd *hcd, struct urb *urb,
		int status)
{
	struct oz_hcd *ozhcd = oz_hcd_private(hcd);
	unsigned long irq_state;
	struct oz_urb_link *cancel_urbl;

	spin_lock_irqsave(&g_tasklet_lock, irq_state);
	usb_hcd_unlink_urb_from_ep(hcd, urb);
	/* Clear hcpriv which will prevent it being put in the cancel list
	 * in the event that an attempt is made to cancel it.
	 */
	urb->hcpriv = NULL;
	/* Walk the cancel list in case the urb is already sitting there.
	 * Since we process the cancel list in a tasklet rather than in
	 * the dequeue function this could happen.
	 */
	cancel_urbl = oz_uncancel_urb(ozhcd, urb);
	/* Note: we release lock but do not enable local irqs.
	 * It appears that usb_hcd_giveback_urb() expects irqs to be disabled,
	 * or at least other host controllers disable interrupts at this point
	 * so we do the same. We must, however, release the lock otherwise a
	 * deadlock will occur if an urb is submitted to our driver in the urb
	 * completion function. Because we disable interrupts it is possible
	 * that the urb_enqueue function can be called with them disabled.
	 */
	spin_unlock(&g_tasklet_lock);
	if (oz_forget_urb(urb)) {
		oz_dbg(ON, "ERROR Unknown URB %p\n", urb);
	} else {
		atomic_dec(&g_pending_urbs);
		usb_hcd_giveback_urb(hcd, urb, status);
	}
	spin_lock(&g_tasklet_lock);
	spin_unlock_irqrestore(&g_tasklet_lock, irq_state);
	if (cancel_urbl)
		oz_free_urb_link(cancel_urbl);
}

/*
 * Deallocates an endpoint including deallocating any associated stream and
 * returning any queued urbs to the core.
 * Context: softirq
 */
static void oz_ep_free(struct oz_port *port, struct oz_endpoint *ep)
{
	if (port) {
		struct list_head list;
		struct oz_hcd *ozhcd = port->ozhcd;
		INIT_LIST_HEAD(&list);
		if (ep->flags & OZ_F_EP_HAVE_STREAM)
			oz_usb_stream_delete(port->hpd, ep->ep_num);
		/* Transfer URBs to the orphanage while we hold the lock. */
		spin_lock_bh(&ozhcd->hcd_lock);
		/* Note: this works even if ep->urb_list is empty.*/
		list_replace_init(&ep->urb_list, &list);
		/* Put the URBs in the orphanage. */
		list_splice_tail(&list, &ozhcd->orphanage);
		spin_unlock_bh(&ozhcd->hcd_lock);
	}
	oz_dbg(ON, "Freeing endpoint memory\n");
	kfree(ep);
}

/*
 * Context: softirq
 */
static void oz_complete_buffered_urb(struct oz_port *port,
			struct oz_endpoint *ep,
			struct urb *urb)
{
	int data_len, available_space, copy_len;

	data_len = ep->buffer[ep->out_ix];
	if (data_len <= urb->transfer_buffer_length)
		available_space = data_len;
	else
		available_space = urb->transfer_buffer_length;

	if (++ep->out_ix == ep->buffer_size)
		ep->out_ix = 0;
	copy_len = ep->buffer_size - ep->out_ix;
	if (copy_len >= available_space)
		copy_len = available_space;
	memcpy(urb->transfer_buffer, &ep->buffer[ep->out_ix], copy_len);

	if (copy_len < available_space) {
		memcpy((urb->transfer_buffer + copy_len), ep->buffer,
						(available_space - copy_len));
		ep->out_ix = available_space - copy_len;
	} else {
		ep->out_ix += copy_len;
	}
	urb->actual_length = available_space;
	if (ep->out_ix == ep->buffer_size)
		ep->out_ix = 0;

	ep->buffered_units--;
	oz_dbg(ON, "Trying to give back buffered frame of size=%d\n",
	       available_space);
	oz_complete_urb(port->ozhcd->hcd, urb, 0);
}

/*
 * Context: softirq
 */
static int oz_enqueue_ep_urb(struct oz_port *port, u8 ep_addr, int in_dir,
			struct urb *urb, u8 req_id)
{
	struct oz_urb_link *urbl;
	struct oz_endpoint *ep = NULL;
	int err = 0;

	if (ep_addr >= OZ_NB_ENDPOINTS) {
		oz_dbg(ON, "%s: Invalid endpoint number\n", __func__);
		return -EINVAL;
	}
	urbl = oz_alloc_urb_link();
	if (!urbl)
		return -ENOMEM;
	urbl->submit_counter = 0;
	urbl->urb = urb;
	urbl->req_id = req_id;
	urbl->ep_num = ep_addr;
	/* Hold lock while we insert the URB into the list within the
	 * endpoint structure.
	 */
	spin_lock_bh(&port->ozhcd->hcd_lock);
	/* If the urb has been unlinked while out of any list then
	 * complete it now.
	 */
	if (urb->unlinked) {
		spin_unlock_bh(&port->ozhcd->hcd_lock);
		oz_dbg(ON, "urb %p unlinked so complete immediately\n", urb);
		oz_complete_urb(port->ozhcd->hcd, urb, 0);
		oz_free_urb_link(urbl);
		return 0;
	}

	if (in_dir)
		ep = port->in_ep[ep_addr];
	else
		ep = port->out_ep[ep_addr];
	if (!ep) {
		err = -ENOMEM;
		goto out;
	}

	/*For interrupt endpoint check for buffered data
	* & complete urb
	*/
	if (((ep->attrib & USB_ENDPOINT_XFERTYPE_MASK) == USB_ENDPOINT_XFER_INT)
						 && ep->buffered_units > 0) {
		oz_free_urb_link(urbl);
		spin_unlock_bh(&port->ozhcd->hcd_lock);
		oz_complete_buffered_urb(port, ep, urb);
		return 0;
	}

	if (port->hpd) {
		list_add_tail(&urbl->link, &ep->urb_list);
		if (!in_dir && ep_addr && (ep->credit < 0)) {
			getrawmonotonic(&ep->timestamp);
			ep->credit = 0;
		}
	} else {
		err = -EPIPE;
	}
out:
	spin_unlock_bh(&port->ozhcd->hcd_lock);
	if (err)
		oz_free_urb_link(urbl);
	return err;
}

/*
 * Removes an urb from the queue in the endpoint.
 * Returns 0 if it is found and -EIDRM otherwise.
 * Context: softirq
 */
static int oz_dequeue_ep_urb(struct oz_port *port, u8 ep_addr, int in_dir,
			struct urb *urb)
{
	struct oz_urb_link *urbl = NULL;
	struct oz_endpoint *ep;

	spin_lock_bh(&port->ozhcd->hcd_lock);
	if (in_dir)
		ep = port->in_ep[ep_addr];
	else
		ep = port->out_ep[ep_addr];
	if (ep) {
		struct list_head *e;
		list_for_each(e, &ep->urb_list) {
			urbl = container_of(e, struct oz_urb_link, link);
			if (urbl->urb == urb) {
				list_del_init(e);
				break;
			}
			urbl = NULL;
		}
	}
	spin_unlock_bh(&port->ozhcd->hcd_lock);
	if (urbl)
		oz_free_urb_link(urbl);
	return urbl ? 0 : -EIDRM;
}

/*
 * Finds an urb given its request id.
 * Context: softirq
 */
static struct urb *oz_find_urb_by_id(struct oz_port *port, int ep_ix,
		u8 req_id)
{
	struct oz_hcd *ozhcd = port->ozhcd;
	struct urb *urb = NULL;
	struct oz_urb_link *urbl;
	struct oz_endpoint *ep;

	spin_lock_bh(&ozhcd->hcd_lock);
	ep = port->out_ep[ep_ix];
	if (ep) {
		struct list_head *e;
		list_for_each(e, &ep->urb_list) {
			urbl = container_of(e, struct oz_urb_link, link);
			if (urbl->req_id == req_id) {
				urb = urbl->urb;
				list_del_init(e);
				break;
			}
		}
	}
	spin_unlock_bh(&ozhcd->hcd_lock);
	/* If urb is non-zero then we we must have an urb link to delete.
	 */
	if (urb)
		oz_free_urb_link(urbl);
	return urb;
}

/*
 * Pre-condition: Port lock must be held.
 * Context: softirq
 */
static void oz_acquire_port(struct oz_port *port, void *hpd)
{
	INIT_LIST_HEAD(&port->isoc_out_ep);
	INIT_LIST_HEAD(&port->isoc_in_ep);
	port->flags |= OZ_PORT_F_PRESENT | OZ_PORT_F_CHANGED;
	port->status |= USB_PORT_STAT_CONNECTION |
			(USB_PORT_STAT_C_CONNECTION << 16);
	oz_usb_get(hpd);
	port->hpd = hpd;
}

/*
 * Context: softirq
 */
static struct oz_hcd *oz_hcd_claim(void)
{
	struct oz_hcd *ozhcd;

	spin_lock_bh(&g_hcdlock);
	ozhcd = g_ozhcd;
	if (ozhcd)
		usb_get_hcd(ozhcd->hcd);
	spin_unlock_bh(&g_hcdlock);
	return ozhcd;
}

/*
 * Context: softirq
 */
static inline void oz_hcd_put(struct oz_hcd *ozhcd)
{
	if (ozhcd)
		usb_put_hcd(ozhcd->hcd);
}

/*
 * This is called by the protocol handler to notify that a PD has arrived.
 * We allocate a port to associate with the PD and create a structure for
 * endpoint 0. This port is made the connection port.
 * In the event that one of the other port is already a connection port then
 * we fail.
 * TODO We should be able to do better than fail and should be able remember
 * that this port needs configuring and make it the connection port once the
 * current connection port has been assigned an address. Collisions here are
 * probably very rare indeed.
 * Context: softirq
 */
struct oz_port *oz_hcd_pd_arrived(void *hpd)
{
	int i;
	struct oz_port *hport;
	struct oz_hcd *ozhcd;
	struct oz_endpoint *ep;

	ozhcd = oz_hcd_claim();
	if (!ozhcd)
		return NULL;
	/* Allocate an endpoint object in advance (before holding hcd lock) to
	 * use for out endpoint 0.
	 */
	ep = oz_ep_alloc(0, GFP_ATOMIC);
	if (!ep)
		goto err_put;

	spin_lock_bh(&ozhcd->hcd_lock);
	if (ozhcd->conn_port >= 0)
		goto err_unlock;

	for (i = 0; i < OZ_NB_PORTS; i++) {
		struct oz_port *port = &ozhcd->ports[i];

		spin_lock(&port->port_lock);
		if (!(port->flags & (OZ_PORT_F_PRESENT | OZ_PORT_F_CHANGED))) {
			oz_acquire_port(port, hpd);
			spin_unlock(&port->port_lock);
			break;
		}
		spin_unlock(&port->port_lock);
	}
	if (i == OZ_NB_PORTS)
		goto err_unlock;

	ozhcd->conn_port = i;
	hport = &ozhcd->ports[i];
	hport->out_ep[0] = ep;
	spin_unlock_bh(&ozhcd->hcd_lock);
	if (ozhcd->flags & OZ_HDC_F_SUSPENDED)
		usb_hcd_resume_root_hub(ozhcd->hcd);
	usb_hcd_poll_rh_status(ozhcd->hcd);
	oz_hcd_put(ozhcd);

	return hport;

err_unlock:
	spin_unlock_bh(&ozhcd->hcd_lock);
	oz_ep_free(NULL, ep);
err_put:
	oz_hcd_put(ozhcd);
	return NULL;
}

/*
 * This is called by the protocol handler to notify that the PD has gone away.
 * We need to deallocate all resources and then request that the root hub is
 * polled. We release the reference we hold on the PD.
 * Context: softirq
 */
void oz_hcd_pd_departed(struct oz_port *port)
{
	struct oz_hcd *ozhcd;
	void *hpd;
	struct oz_endpoint *ep = NULL;

	if (port == NULL) {
		oz_dbg(ON, "%s: port = 0\n", __func__);
		return;
	}
	ozhcd = port->ozhcd;
	if (ozhcd == NULL)
		return;
	/* Check if this is the connection port - if so clear it.
	 */
	spin_lock_bh(&ozhcd->hcd_lock);
	if ((ozhcd->conn_port >= 0) &&
		(port == &ozhcd->ports[ozhcd->conn_port])) {
		oz_dbg(ON, "Clearing conn_port\n");
		ozhcd->conn_port = -1;
	}
	spin_lock(&port->port_lock);
	port->flags |= OZ_PORT_F_DYING;
	spin_unlock(&port->port_lock);
	spin_unlock_bh(&ozhcd->hcd_lock);

	oz_clean_endpoints_for_config(ozhcd->hcd, port);
	spin_lock_bh(&port->port_lock);
	hpd = port->hpd;
	port->hpd = NULL;
	port->bus_addr = 0xff;
	port->config_num = 0;
	port->flags &= ~(OZ_PORT_F_PRESENT | OZ_PORT_F_DYING);
	port->flags |= OZ_PORT_F_CHANGED;
	port->status &= ~(USB_PORT_STAT_CONNECTION | USB_PORT_STAT_ENABLE);
	port->status |= (USB_PORT_STAT_C_CONNECTION << 16);
	/* If there is an endpont 0 then clear the pointer while we hold
	 * the spinlock be we deallocate it after releasing the lock.
	 */
	if (port->out_ep[0]) {
		ep = port->out_ep[0];
		port->out_ep[0] = NULL;
	}
	spin_unlock_bh(&port->port_lock);
	if (ep)
		oz_ep_free(port, ep);
	usb_hcd_poll_rh_status(ozhcd->hcd);
	oz_usb_put(hpd);
}

/*
 * Context: softirq
 */
void oz_hcd_pd_reset(void *hpd, void *hport)
{
	/* Cleanup the current configuration and report reset to the core.
	 */
	struct oz_port *port = (struct oz_port *)hport;
	struct oz_hcd *ozhcd = port->ozhcd;

	oz_dbg(ON, "PD Reset\n");
	spin_lock_bh(&port->port_lock);
	port->flags |= OZ_PORT_F_CHANGED;
	port->status |= USB_PORT_STAT_RESET;
	port->status |= (USB_PORT_STAT_C_RESET << 16);
	spin_unlock_bh(&port->port_lock);
	oz_clean_endpoints_for_config(ozhcd->hcd, port);
	usb_hcd_poll_rh_status(ozhcd->hcd);
}

/*
 * Context: softirq
 */
void oz_hcd_get_desc_cnf(void *hport, u8 req_id, int status, const u8 *desc,
			int length, int offset, int total_size)
{
	struct oz_port *port = (struct oz_port *)hport;
	struct urb *urb;
	int err = 0;

	oz_dbg(ON, "oz_hcd_get_desc_cnf length = %d offs = %d tot_size = %d\n",
	       length, offset, total_size);
	urb = oz_find_urb_by_id(port, 0, req_id);
	if (!urb)
		return;
	if (status == 0) {
		int copy_len;
		int required_size = urb->transfer_buffer_length;
		if (required_size > total_size)
			required_size = total_size;
		copy_len = required_size-offset;
		if (length <= copy_len)
			copy_len = length;
		memcpy(urb->transfer_buffer+offset, desc, copy_len);
		offset += copy_len;
		if (offset < required_size) {
			struct usb_ctrlrequest *setup =
				(struct usb_ctrlrequest *)urb->setup_packet;
			unsigned wvalue = le16_to_cpu(setup->wValue);
			if (oz_enqueue_ep_urb(port, 0, 0, urb, req_id))
				err = -ENOMEM;
			else if (oz_usb_get_desc_req(port->hpd, req_id,
					setup->bRequestType, (u8)(wvalue>>8),
					(u8)wvalue, setup->wIndex, offset,
					required_size-offset)) {
				oz_dequeue_ep_urb(port, 0, 0, urb);
				err = -ENOMEM;
			}
			if (err == 0)
				return;
		}
	}
	urb->actual_length = total_size;
	oz_complete_urb(port->ozhcd->hcd, urb, 0);
}

/*
 * Context: softirq
 */
static void oz_display_conf_type(u8 t)
{
	switch (t) {
	case USB_REQ_GET_STATUS:
		oz_dbg(ON, "USB_REQ_GET_STATUS - cnf\n");
		break;
	case USB_REQ_CLEAR_FEATURE:
		oz_dbg(ON, "USB_REQ_CLEAR_FEATURE - cnf\n");
		break;
	case USB_REQ_SET_FEATURE:
		oz_dbg(ON, "USB_REQ_SET_FEATURE - cnf\n");
		break;
	case USB_REQ_SET_ADDRESS:
		oz_dbg(ON, "USB_REQ_SET_ADDRESS - cnf\n");
		break;
	case USB_REQ_GET_DESCRIPTOR:
		oz_dbg(ON, "USB_REQ_GET_DESCRIPTOR - cnf\n");
		break;
	case USB_REQ_SET_DESCRIPTOR:
		oz_dbg(ON, "USB_REQ_SET_DESCRIPTOR - cnf\n");
		break;
	case USB_REQ_GET_CONFIGURATION:
		oz_dbg(ON, "USB_REQ_GET_CONFIGURATION - cnf\n");
		break;
	case USB_REQ_SET_CONFIGURATION:
		oz_dbg(ON, "USB_REQ_SET_CONFIGURATION - cnf\n");
		break;
	case USB_REQ_GET_INTERFACE:
		oz_dbg(ON, "USB_REQ_GET_INTERFACE - cnf\n");
		break;
	case USB_REQ_SET_INTERFACE:
		oz_dbg(ON, "USB_REQ_SET_INTERFACE - cnf\n");
		break;
	case USB_REQ_SYNCH_FRAME:
		oz_dbg(ON, "USB_REQ_SYNCH_FRAME - cnf\n");
		break;
	}
}

/*
 * Context: softirq
 */
static void oz_hcd_complete_set_config(struct oz_port *port, struct urb *urb,
		u8 rcode, u8 config_num)
{
	int rc = 0;
	struct usb_hcd *hcd = port->ozhcd->hcd;

	if (rcode == 0) {
		port->config_num = config_num;
		oz_clean_endpoints_for_config(hcd, port);
		if (oz_build_endpoints_for_config(hcd, port,
			&urb->dev->config[port->config_num-1], GFP_ATOMIC)) {
			rc = -ENOMEM;
		}
	} else {
		rc = -ENOMEM;
	}
	oz_complete_urb(hcd, urb, rc);
}

/*
 * Context: softirq
 */
static void oz_hcd_complete_set_interface(struct oz_port *port, struct urb *urb,
		u8 rcode, u8 if_num, u8 alt)
{
	struct usb_hcd *hcd = port->ozhcd->hcd;
	int rc = 0;

	if ((rcode == 0) && (port->config_num > 0)) {
		struct usb_host_config *config;
		struct usb_host_interface *intf;
		oz_dbg(ON, "Set interface %d alt %d\n", if_num, alt);
		oz_clean_endpoints_for_interface(hcd, port, if_num);
		config = &urb->dev->config[port->config_num-1];
		intf = &config->intf_cache[if_num]->altsetting[alt];
		if (oz_build_endpoints_for_interface(hcd, port, intf,
			GFP_ATOMIC))
			rc = -ENOMEM;
		else
			port->iface[if_num].alt = alt;
	} else {
		rc = -ENOMEM;
	}
	oz_complete_urb(hcd, urb, rc);
}

/*
 * Context: softirq
 */
void oz_hcd_control_cnf(void *hport, u8 req_id, u8 rcode, const u8 *data,
	int data_len)
{
	struct oz_port *port = (struct oz_port *)hport;
	struct urb *urb;
	struct usb_ctrlrequest *setup;
	struct usb_hcd *hcd = port->ozhcd->hcd;
	unsigned windex;
	unsigned wvalue;

	oz_dbg(ON, "oz_hcd_control_cnf rcode=%u len=%d\n", rcode, data_len);
	urb = oz_find_urb_by_id(port, 0, req_id);
	if (!urb) {
		oz_dbg(ON, "URB not found\n");
		return;
	}
	setup = (struct usb_ctrlrequest *)urb->setup_packet;
	windex = le16_to_cpu(setup->wIndex);
	wvalue = le16_to_cpu(setup->wValue);
	if ((setup->bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD) {
		/* Standard requests */
		oz_display_conf_type(setup->bRequest);
		switch (setup->bRequest) {
		case USB_REQ_SET_CONFIGURATION:
			oz_hcd_complete_set_config(port, urb, rcode,
				(u8)wvalue);
			break;
		case USB_REQ_SET_INTERFACE:
			oz_hcd_complete_set_interface(port, urb, rcode,
				(u8)windex, (u8)wvalue);
			break;
		default:
			oz_complete_urb(hcd, urb, 0);
		}

	} else {
		int copy_len;
		oz_dbg(ON, "VENDOR-CLASS - cnf\n");
		if (data_len) {
			if (data_len <= urb->transfer_buffer_length)
				copy_len = data_len;
			else
				copy_len = urb->transfer_buffer_length;
			memcpy(urb->transfer_buffer, data, copy_len);
			urb->actual_length = copy_len;
		}
		oz_complete_urb(hcd, urb, 0);
	}
}

/*
 * Context: softirq-serialized
 */
static int oz_hcd_buffer_data(struct oz_endpoint *ep, const u8 *data,
			      int data_len)
{
	int space;
	int copy_len;

	if (!ep->buffer)
		return -1;
	space = ep->out_ix-ep->in_ix-1;
	if (space < 0)
		space += ep->buffer_size;
	if (space < (data_len+1)) {
		oz_dbg(ON, "Buffer full\n");
		return -1;
	}
	ep->buffer[ep->in_ix] = (u8)data_len;
	if (++ep->in_ix == ep->buffer_size)
		ep->in_ix = 0;
	copy_len = ep->buffer_size - ep->in_ix;
	if (copy_len > data_len)
		copy_len = data_len;
	memcpy(&ep->buffer[ep->in_ix], data, copy_len);

	if (copy_len < data_len) {
		memcpy(ep->buffer, data+copy_len, data_len-copy_len);
		ep->in_ix = data_len-copy_len;
	} else {
		ep->in_ix += copy_len;
	}
	if (ep->in_ix == ep->buffer_size)
		ep->in_ix = 0;
	ep->buffered_units++;
	return 0;
}

/*
 * Context: softirq-serialized
 */
void oz_hcd_data_ind(void *hport, u8 endpoint, const u8 *data, int data_len)
{
	struct oz_port *port = (struct oz_port *)hport;
	struct oz_endpoint *ep;
	struct oz_hcd *ozhcd = port->ozhcd;

	spin_lock_bh(&ozhcd->hcd_lock);
	ep = port->in_ep[endpoint & USB_ENDPOINT_NUMBER_MASK];
	if (ep == NULL)
		goto done;
	switch (ep->attrib & USB_ENDPOINT_XFERTYPE_MASK) {
	case USB_ENDPOINT_XFER_INT:
	case USB_ENDPOINT_XFER_BULK:
		if (!list_empty(&ep->urb_list)) {
			struct oz_urb_link *urbl =
				list_first_entry(&ep->urb_list,
					struct oz_urb_link, link);
			struct urb *urb;
			int copy_len;
			list_del_init(&urbl->link);
			spin_unlock_bh(&ozhcd->hcd_lock);
			urb = urbl->urb;
			oz_free_urb_link(urbl);
			if (data_len <= urb->transfer_buffer_length)
				copy_len = data_len;
			else
				copy_len = urb->transfer_buffer_length;
			memcpy(urb->transfer_buffer, data, copy_len);
			urb->actual_length = copy_len;
			oz_complete_urb(port->ozhcd->hcd, urb, 0);
			return;
		} else {
			oz_dbg(ON, "buffering frame as URB is not available\n");
			oz_hcd_buffer_data(ep, data, data_len);
		}
		break;
	case USB_ENDPOINT_XFER_ISOC:
		oz_hcd_buffer_data(ep, data, data_len);
		break;
	}
done:
	spin_unlock_bh(&ozhcd->hcd_lock);
}

/*
 * Context: unknown
 */
static inline int oz_usb_get_frame_number(void)
{
	return atomic_inc_return(&g_usb_frame_number);
}

/*
 * Context: softirq
 */
int oz_hcd_heartbeat(void *hport)
{
	int rc = 0;
	struct oz_port *port = (struct oz_port *)hport;
	struct oz_hcd *ozhcd = port->ozhcd;
	struct oz_urb_link *urbl;
	struct list_head xfr_list;
	struct list_head *e;
	struct list_head *n;
	struct urb *urb;
	struct oz_endpoint *ep;
	struct timespec ts, delta;

	getrawmonotonic(&ts);
	INIT_LIST_HEAD(&xfr_list);
	/* Check the OUT isoc endpoints to see if any URB data can be sent.
	 */
	spin_lock_bh(&ozhcd->hcd_lock);
	list_for_each(e, &port->isoc_out_ep) {
		ep = ep_from_link(e);
		if (ep->credit < 0)
			continue;
		delta = timespec_sub(ts, ep->timestamp);
		ep->credit += div_u64(timespec_to_ns(&delta), NSEC_PER_MSEC);
		if (ep->credit > ep->credit_ceiling)
			ep->credit = ep->credit_ceiling;
		ep->timestamp = ts;
		while (ep->credit && !list_empty(&ep->urb_list)) {
			urbl = list_first_entry(&ep->urb_list,
				struct oz_urb_link, link);
			urb = urbl->urb;
			if ((ep->credit + 1) < urb->number_of_packets)
				break;
			ep->credit -= urb->number_of_packets;
			if (ep->credit < 0)
				ep->credit = 0;
			list_move_tail(&urbl->link, &xfr_list);
		}
	}
	spin_unlock_bh(&ozhcd->hcd_lock);
	/* Send to PD and complete URBs.
	 */
	list_for_each_safe(e, n, &xfr_list) {
		urbl = container_of(e, struct oz_urb_link, link);
		urb = urbl->urb;
		list_del_init(e);
		urb->error_count = 0;
		urb->start_frame = oz_usb_get_frame_number();
		oz_usb_send_isoc(port->hpd, urbl->ep_num, urb);
		oz_free_urb_link(urbl);
		oz_complete_urb(port->ozhcd->hcd, urb, 0);
	}
	/* Check the IN isoc endpoints to see if any URBs can be completed.
	 */
	spin_lock_bh(&ozhcd->hcd_lock);
	list_for_each(e, &port->isoc_in_ep) {
		struct oz_endpoint *ep = ep_from_link(e);
		if (ep->flags & OZ_F_EP_BUFFERING) {
			if (ep->buffered_units >= OZ_IN_BUFFERING_UNITS) {
				ep->flags &= ~OZ_F_EP_BUFFERING;
				ep->credit = 0;
				ep->timestamp = ts;
				ep->start_frame = 0;
			}
			continue;
		}
		delta = timespec_sub(ts, ep->timestamp);
		ep->credit += div_u64(timespec_to_ns(&delta), NSEC_PER_MSEC);
		ep->timestamp = ts;
		while (!list_empty(&ep->urb_list)) {
			struct oz_urb_link *urbl =
				list_first_entry(&ep->urb_list,
					struct oz_urb_link, link);
			struct urb *urb = urbl->urb;
			int len = 0;
			int copy_len;
			int i;
			if (ep->credit  < urb->number_of_packets)
				break;
			if (ep->buffered_units < urb->number_of_packets)
				break;
			urb->actual_length = 0;
			for (i = 0; i < urb->number_of_packets; i++) {
				len = ep->buffer[ep->out_ix];
				if (++ep->out_ix == ep->buffer_size)
					ep->out_ix = 0;
				copy_len = ep->buffer_size - ep->out_ix;
				if (copy_len > len)
					copy_len = len;
				memcpy(urb->transfer_buffer,
					&ep->buffer[ep->out_ix], copy_len);
				if (copy_len < len) {
					memcpy(urb->transfer_buffer+copy_len,
						ep->buffer, len-copy_len);
					ep->out_ix = len-copy_len;
				} else
					ep->out_ix += copy_len;
				if (ep->out_ix == ep->buffer_size)
					ep->out_ix = 0;
				urb->iso_frame_desc[i].offset =
					urb->actual_length;
				urb->actual_length += len;
				urb->iso_frame_desc[i].actual_length = len;
				urb->iso_frame_desc[i].status = 0;
			}
			ep->buffered_units -= urb->number_of_packets;
			urb->error_count = 0;
			urb->start_frame = ep->start_frame;
			ep->start_frame += urb->number_of_packets;
			list_move_tail(&urbl->link, &xfr_list);
			ep->credit -= urb->number_of_packets;
		}
	}
	if (!list_empty(&port->isoc_out_ep) || !list_empty(&port->isoc_in_ep))
		rc = 1;
	spin_unlock_bh(&ozhcd->hcd_lock);
	/* Complete the filled URBs.
	 */
	list_for_each_safe(e, n, &xfr_list) {
		urbl = container_of(e, struct oz_urb_link, link);
		urb = urbl->urb;
		list_del_init(e);
		oz_free_urb_link(urbl);
		oz_complete_urb(port->ozhcd->hcd, urb, 0);
	}
	/* Check if there are any ep0 requests that have timed out.
	 * If so resent to PD.
	 */
	ep = port->out_ep[0];
	if (ep) {
		struct list_head *e;
		struct list_head *n;
		spin_lock_bh(&ozhcd->hcd_lock);
		list_for_each_safe(e, n, &ep->urb_list) {
			urbl = container_of(e, struct oz_urb_link, link);
			if (urbl->submit_counter > EP0_TIMEOUT_COUNTER) {
				oz_dbg(ON, "Request 0x%p timeout\n", urbl->urb);
				list_move_tail(e, &xfr_list);
				urbl->submit_counter = 0;
			} else {
				urbl->submit_counter++;
			}
		}
		if (!list_empty(&ep->urb_list))
			rc = 1;
		spin_unlock_bh(&ozhcd->hcd_lock);
		e = xfr_list.next;
		while (e != &xfr_list) {
			urbl = container_of(e, struct oz_urb_link, link);
			e = e->next;
			oz_dbg(ON, "Resending request to PD\n");
			oz_process_ep0_urb(ozhcd, urbl->urb, GFP_ATOMIC);
			oz_free_urb_link(urbl);
		}
	}
	return rc;
}

/*
 * Context: softirq
 */
static int oz_build_endpoints_for_interface(struct usb_hcd *hcd,
		struct oz_port *port,
		struct usb_host_interface *intf, gfp_t mem_flags)
{
	struct oz_hcd *ozhcd = port->ozhcd;
	int i;
	int if_ix = intf->desc.bInterfaceNumber;
	int request_heartbeat = 0;

	oz_dbg(ON, "interface[%d] = %p\n", if_ix, intf);
	if (if_ix >= port->num_iface || port->iface == NULL)
		return -ENOMEM;
	for (i = 0; i < intf->desc.bNumEndpoints; i++) {
		struct usb_host_endpoint *hep = &intf->endpoint[i];
		u8 ep_addr = hep->desc.bEndpointAddress;
		u8 ep_num = ep_addr & USB_ENDPOINT_NUMBER_MASK;
		struct oz_endpoint *ep;
		int buffer_size = 0;

		oz_dbg(ON, "%d bEndpointAddress = %x\n", i, ep_addr);
		if (ep_addr & USB_ENDPOINT_DIR_MASK) {
			switch (hep->desc.bmAttributes &
						USB_ENDPOINT_XFERTYPE_MASK) {
			case USB_ENDPOINT_XFER_ISOC:
				buffer_size = OZ_EP_BUFFER_SIZE_ISOC;
				break;
			case USB_ENDPOINT_XFER_INT:
				buffer_size = OZ_EP_BUFFER_SIZE_INT;
				break;
			}
		}

		ep = oz_ep_alloc(buffer_size, mem_flags);
		if (!ep) {
			oz_clean_endpoints_for_interface(hcd, port, if_ix);
			return -ENOMEM;
		}
		ep->attrib = hep->desc.bmAttributes;
		ep->ep_num = ep_num;
		if ((ep->attrib & USB_ENDPOINT_XFERTYPE_MASK)
			== USB_ENDPOINT_XFER_ISOC) {
			oz_dbg(ON, "wMaxPacketSize = %d\n",
			       usb_endpoint_maxp(&hep->desc));
			ep->credit_ceiling = 200;
			if (ep_addr & USB_ENDPOINT_DIR_MASK) {
				ep->flags |= OZ_F_EP_BUFFERING;
			} else {
				ep->flags |= OZ_F_EP_HAVE_STREAM;
				if (oz_usb_stream_create(port->hpd, ep_num))
					ep->flags &= ~OZ_F_EP_HAVE_STREAM;
			}
		}
		spin_lock_bh(&ozhcd->hcd_lock);
		if (ep_addr & USB_ENDPOINT_DIR_MASK) {
			port->in_ep[ep_num] = ep;
			port->iface[if_ix].ep_mask |=
				(1<<(ep_num+OZ_NB_ENDPOINTS));
			if ((ep->attrib & USB_ENDPOINT_XFERTYPE_MASK)
				 == USB_ENDPOINT_XFER_ISOC) {
				list_add_tail(&ep->link, &port->isoc_in_ep);
				request_heartbeat = 1;
			}
		} else {
			port->out_ep[ep_num] = ep;
			port->iface[if_ix].ep_mask |= (1<<ep_num);
			if ((ep->attrib & USB_ENDPOINT_XFERTYPE_MASK)
				== USB_ENDPOINT_XFER_ISOC) {
				list_add_tail(&ep->link, &port->isoc_out_ep);
				request_heartbeat = 1;
			}
		}
		spin_unlock_bh(&ozhcd->hcd_lock);
		if (request_heartbeat && port->hpd)
			oz_usb_request_heartbeat(port->hpd);
	}
	return 0;
}

/*
 * Context: softirq
 */
static void oz_clean_endpoints_for_interface(struct usb_hcd *hcd,
			struct oz_port *port, int if_ix)
{
	struct oz_hcd *ozhcd = port->ozhcd;
	unsigned mask;
	int i;
	struct list_head ep_list;

	oz_dbg(ON, "Deleting endpoints for interface %d\n", if_ix);
	if (if_ix >= port->num_iface)
		return;
	INIT_LIST_HEAD(&ep_list);
	spin_lock_bh(&ozhcd->hcd_lock);
	mask = port->iface[if_ix].ep_mask;
	port->iface[if_ix].ep_mask = 0;
	for (i = 0; i < OZ_NB_ENDPOINTS; i++) {
		struct list_head *e;
		/* Gather OUT endpoints.
		 */
		if ((mask & (1<<i)) && port->out_ep[i]) {
			e = &port->out_ep[i]->link;
			port->out_ep[i] = NULL;
			/* Remove from isoc list if present.
			 */
			list_move_tail(e, &ep_list);
		}
		/* Gather IN endpoints.
		 */
		if ((mask & (1<<(i+OZ_NB_ENDPOINTS))) && port->in_ep[i]) {
			e = &port->in_ep[i]->link;
			port->in_ep[i] = NULL;
			list_move_tail(e, &ep_list);
		}
	}
	spin_unlock_bh(&ozhcd->hcd_lock);
	while (!list_empty(&ep_list)) {
		struct oz_endpoint *ep =
			list_first_entry(&ep_list, struct oz_endpoint, link);
		list_del_init(&ep->link);
		oz_ep_free(port, ep);
	}
}

/*
 * Context: softirq
 */
static int oz_build_endpoints_for_config(struct usb_hcd *hcd,
		struct oz_port *port, struct usb_host_config *config,
		gfp_t mem_flags)
{
	struct oz_hcd *ozhcd = port->ozhcd;
	int i;
	int num_iface = config->desc.bNumInterfaces;

	if (num_iface) {
		struct oz_interface *iface;

		iface = kmalloc(num_iface*sizeof(struct oz_interface),
				mem_flags | __GFP_ZERO);
		if (!iface)
			return -ENOMEM;
		spin_lock_bh(&ozhcd->hcd_lock);
		port->iface = iface;
		port->num_iface = num_iface;
		spin_unlock_bh(&ozhcd->hcd_lock);
	}
	for (i = 0; i < num_iface; i++) {
		struct usb_host_interface *intf =
			&config->intf_cache[i]->altsetting[0];
		if (oz_build_endpoints_for_interface(hcd, port, intf,
			mem_flags))
			goto fail;
	}
	return 0;
fail:
	oz_clean_endpoints_for_config(hcd, port);
	return -1;
}

/*
 * Context: softirq
 */
static void oz_clean_endpoints_for_config(struct usb_hcd *hcd,
			struct oz_port *port)
{
	struct oz_hcd *ozhcd = port->ozhcd;
	int i;

	oz_dbg(ON, "Deleting endpoints for configuration\n");
	for (i = 0; i < port->num_iface; i++)
		oz_clean_endpoints_for_interface(hcd, port, i);
	spin_lock_bh(&ozhcd->hcd_lock);
	if (port->iface) {
		oz_dbg(ON, "Freeing interfaces object\n");
		kfree(port->iface);
		port->iface = NULL;
	}
	port->num_iface = 0;
	spin_unlock_bh(&ozhcd->hcd_lock);
}

/*
 * Context: tasklet
 */
static void *oz_claim_hpd(struct oz_port *port)
{
	void *hpd;
	struct oz_hcd *ozhcd = port->ozhcd;

	spin_lock_bh(&ozhcd->hcd_lock);
	hpd = port->hpd;
	if (hpd)
		oz_usb_get(hpd);
	spin_unlock_bh(&ozhcd->hcd_lock);
	return hpd;
}

/*
 * Context: tasklet
 */
static void oz_process_ep0_urb(struct oz_hcd *ozhcd, struct urb *urb,
		gfp_t mem_flags)
{
	struct usb_ctrlrequest *setup;
	unsigned windex;
	unsigned wvalue;
	unsigned wlength;
	void *hpd;
	u8 req_id;
	int rc = 0;
	unsigned complete = 0;

	int port_ix = -1;
	struct oz_port *port = NULL;

	oz_dbg(URB, "[%s]:(%p)\n", __func__, urb);
	port_ix = oz_get_port_from_addr(ozhcd, urb->dev->devnum);
	if (port_ix < 0) {
		rc = -EPIPE;
		goto out;
	}
	port =  &ozhcd->ports[port_ix];
	if (((port->flags & OZ_PORT_F_PRESENT) == 0)
		|| (port->flags & OZ_PORT_F_DYING)) {
		oz_dbg(ON, "Refusing URB port_ix = %d devnum = %d\n",
		       port_ix, urb->dev->devnum);
		rc = -EPIPE;
		goto out;
	}
	/* Store port in private context data.
	 */
	urb->hcpriv = port;
	setup = (struct usb_ctrlrequest *)urb->setup_packet;
	windex = le16_to_cpu(setup->wIndex);
	wvalue = le16_to_cpu(setup->wValue);
	wlength = le16_to_cpu(setup->wLength);
	oz_dbg(CTRL_DETAIL, "bRequestType = %x\n", setup->bRequestType);
	oz_dbg(CTRL_DETAIL, "bRequest = %x\n", setup->bRequest);
	oz_dbg(CTRL_DETAIL, "wValue = %x\n", wvalue);
	oz_dbg(CTRL_DETAIL, "wIndex = %x\n", windex);
	oz_dbg(CTRL_DETAIL, "wLength = %x\n", wlength);

	req_id = port->next_req_id++;
	hpd = oz_claim_hpd(port);
	if (hpd == NULL) {
		oz_dbg(ON, "Cannot claim port\n");
		rc = -EPIPE;
		goto out;
	}

	if ((setup->bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD) {
		/* Standard requests
		 */
		switch (setup->bRequest) {
		case USB_REQ_GET_DESCRIPTOR:
			oz_dbg(ON, "USB_REQ_GET_DESCRIPTOR - req\n");
			break;
		case USB_REQ_SET_ADDRESS:
			oz_dbg(ON, "USB_REQ_SET_ADDRESS - req\n");
			oz_dbg(ON, "Port %d address is 0x%x\n",
			       ozhcd->conn_port,
			       (u8)le16_to_cpu(setup->wValue));
			spin_lock_bh(&ozhcd->hcd_lock);
			if (ozhcd->conn_port >= 0) {
				ozhcd->ports[ozhcd->conn_port].bus_addr =
					(u8)le16_to_cpu(setup->wValue);
				oz_dbg(ON, "Clearing conn_port\n");
				ozhcd->conn_port = -1;
			}
			spin_unlock_bh(&ozhcd->hcd_lock);
			complete = 1;
			break;
		case USB_REQ_SET_CONFIGURATION:
			oz_dbg(ON, "USB_REQ_SET_CONFIGURATION - req\n");
			break;
		case USB_REQ_GET_CONFIGURATION:
			/* We short circuit this case and reply directly since
			 * we have the selected configuration number cached.
			 */
			oz_dbg(ON, "USB_REQ_GET_CONFIGURATION - reply now\n");
			if (urb->transfer_buffer_length >= 1) {
				urb->actual_length = 1;
				*((u8 *)urb->transfer_buffer) =
					port->config_num;
				complete = 1;
			} else {
				rc = -EPIPE;
			}
			break;
		case USB_REQ_GET_INTERFACE:
			/* We short circuit this case and reply directly since
			 * we have the selected interface alternative cached.
			 */
			oz_dbg(ON, "USB_REQ_GET_INTERFACE - reply now\n");
			if (urb->transfer_buffer_length >= 1) {
				urb->actual_length = 1;
				*((u8 *)urb->transfer_buffer) =
					port->iface[(u8)windex].alt;
				oz_dbg(ON, "interface = %d alt = %d\n",
				       windex, port->iface[(u8)windex].alt);
				complete = 1;
			} else {
				rc = -EPIPE;
			}
			break;
		case USB_REQ_SET_INTERFACE:
			oz_dbg(ON, "USB_REQ_SET_INTERFACE - req\n");
			break;
		}
	}
	if (!rc && !complete) {
		int data_len = 0;
		if ((setup->bRequestType & USB_DIR_IN) == 0)
			data_len = wlength;
		urb->actual_length = data_len;
		if (oz_usb_control_req(port->hpd, req_id, setup,
				urb->transfer_buffer, data_len)) {
			rc = -ENOMEM;
		} else {
			/* Note: we are queuing the request after we have
			 * submitted it to be transmitted. If the request were
			 * to complete before we queued it then it would not
			 * be found in the queue. It seems impossible for
			 * this to happen but if it did the request would
			 * be resubmitted so the problem would hopefully
			 * resolve itself. Putting the request into the
			 * queue before it has been sent is worse since the
			 * urb could be cancelled while we are using it
			 * to build the request.
			 */
			if (oz_enqueue_ep_urb(port, 0, 0, urb, req_id))
				rc = -ENOMEM;
		}
	}
	oz_usb_put(hpd);
out:
	if (rc || complete) {
		oz_dbg(ON, "Completing request locally\n");
		oz_complete_urb(ozhcd->hcd, urb, rc);
	} else {
		oz_usb_request_heartbeat(port->hpd);
	}
}

/*
 * Context: tasklet
 */
static int oz_urb_process(struct oz_hcd *ozhcd, struct urb *urb)
{
	int rc = 0;
	struct oz_port *port = urb->hcpriv;
	u8 ep_addr;

	/* When we are paranoid we keep a list of urbs which we check against
	 * before handing one back. This is just for debugging during
	 * development and should be turned off in the released driver.
	 */
	oz_remember_urb(urb);
	/* Check buffer is valid.
	 */
	if (!urb->transfer_buffer && urb->transfer_buffer_length)
		return -EINVAL;
	/* Check if there is a device at the port - refuse if not.
	 */
	if ((port->flags & OZ_PORT_F_PRESENT) == 0)
		return -EPIPE;
	ep_addr = usb_pipeendpoint(urb->pipe);
	if (ep_addr) {
		/* If the request is not for EP0 then queue it.
		 */
		if (oz_enqueue_ep_urb(port, ep_addr, usb_pipein(urb->pipe),
			urb, 0))
			rc = -EPIPE;
	} else {
		oz_process_ep0_urb(ozhcd, urb, GFP_ATOMIC);
	}
	return rc;
}

/*
 * Context: tasklet
 */
static void oz_urb_process_tasklet(unsigned long unused)
{
	unsigned long irq_state;
	struct urb *urb;
	struct oz_hcd *ozhcd = oz_hcd_claim();
	int rc = 0;

	if (ozhcd == NULL)
		return;
	/* This is called from a tasklet so is in softirq context but the urb
	 * list is filled from any context so we need to lock
	 * appropriately while removing urbs.
	 */
	spin_lock_irqsave(&g_tasklet_lock, irq_state);
	while (!list_empty(&ozhcd->urb_pending_list)) {
		struct oz_urb_link *urbl =
			list_first_entry(&ozhcd->urb_pending_list,
				struct oz_urb_link, link);
		list_del_init(&urbl->link);
		spin_unlock_irqrestore(&g_tasklet_lock, irq_state);
		urb = urbl->urb;
		oz_free_urb_link(urbl);
		rc = oz_urb_process(ozhcd, urb);
		if (rc)
			oz_complete_urb(ozhcd->hcd, urb, rc);
		spin_lock_irqsave(&g_tasklet_lock, irq_state);
	}
	spin_unlock_irqrestore(&g_tasklet_lock, irq_state);
	oz_hcd_put(ozhcd);
}

/*
 * This function searches for the urb in any of the lists it could be in.
 * If it is found it is removed from the list and completed. If the urb is
 * being processed then it won't be in a list so won't be found. However, the
 * call to usb_hcd_check_unlink_urb() will set the value of the unlinked field
 * to a non-zero value. When an attempt is made to put the urb back in a list
 * the unlinked field will be checked and the urb will then be completed.
 * Context: tasklet
 */
static void oz_urb_cancel(struct oz_port *port, u8 ep_num, struct urb *urb)
{
	struct oz_urb_link *urbl = NULL;
	struct list_head *e;
	struct oz_hcd *ozhcd;
	unsigned long irq_state;
	u8 ix;

	if (port == NULL) {
		oz_dbg(ON, "%s: ERROR: (%p) port is null\n", __func__, urb);
		return;
	}
	ozhcd = port->ozhcd;
	if (ozhcd == NULL) {
		oz_dbg(ON, "%s; ERROR: (%p) ozhcd is null\n", __func__, urb);
		return;
	}

	/* Look in the tasklet queue.
	 */
	spin_lock_irqsave(&g_tasklet_lock, irq_state);
	list_for_each(e, &ozhcd->urb_cancel_list) {
		urbl = container_of(e, struct oz_urb_link, link);
		if (urb == urbl->urb) {
			list_del_init(e);
			spin_unlock_irqrestore(&g_tasklet_lock, irq_state);
			goto out2;
		}
	}
	spin_unlock_irqrestore(&g_tasklet_lock, irq_state);
	urbl = NULL;

	/* Look in the orphanage.
	 */
	spin_lock_irqsave(&ozhcd->hcd_lock, irq_state);
	list_for_each(e, &ozhcd->orphanage) {
		urbl = container_of(e, struct oz_urb_link, link);
		if (urbl->urb == urb) {
			list_del(e);
			oz_dbg(ON, "Found urb in orphanage\n");
			goto out;
		}
	}
	ix = (ep_num & 0xf);
	urbl = NULL;
	if ((ep_num & USB_DIR_IN) && ix)
		urbl = oz_remove_urb(port->in_ep[ix], urb);
	else
		urbl = oz_remove_urb(port->out_ep[ix], urb);
out:
	spin_unlock_irqrestore(&ozhcd->hcd_lock, irq_state);
out2:
	if (urbl) {
		urb->actual_length = 0;
		oz_free_urb_link(urbl);
		oz_complete_urb(ozhcd->hcd, urb, -EPIPE);
	}
}

/*
 * Context: tasklet
 */
static void oz_urb_cancel_tasklet(unsigned long unused)
{
	unsigned long irq_state;
	struct urb *urb;
	struct oz_hcd *ozhcd = oz_hcd_claim();

	if (ozhcd == NULL)
		return;
	spin_lock_irqsave(&g_tasklet_lock, irq_state);
	while (!list_empty(&ozhcd->urb_cancel_list)) {
		struct oz_urb_link *urbl =
			list_first_entry(&ozhcd->urb_cancel_list,
				struct oz_urb_link, link);
		list_del_init(&urbl->link);
		spin_unlock_irqrestore(&g_tasklet_lock, irq_state);
		urb = urbl->urb;
		if (urb->unlinked)
			oz_urb_cancel(urbl->port, urbl->ep_num, urb);
		oz_free_urb_link(urbl);
		spin_lock_irqsave(&g_tasklet_lock, irq_state);
	}
	spin_unlock_irqrestore(&g_tasklet_lock, irq_state);
	oz_hcd_put(ozhcd);
}

/*
 * Context: unknown
 */
static void oz_hcd_clear_orphanage(struct oz_hcd *ozhcd, int status)
{
	if (ozhcd) {
		struct oz_urb_link *urbl;
		while (!list_empty(&ozhcd->orphanage)) {
			urbl = list_first_entry(&ozhcd->orphanage,
				struct oz_urb_link, link);
			list_del(&urbl->link);
			oz_complete_urb(ozhcd->hcd, urbl->urb, status);
			oz_free_urb_link(urbl);
		}
	}
}

/*
 * Context: unknown
 */
static int oz_hcd_start(struct usb_hcd *hcd)
{
	hcd->power_budget = 200;
	hcd->state = HC_STATE_RUNNING;
	hcd->uses_new_polling = 1;
	return 0;
}

/*
 * Context: unknown
 */
static void oz_hcd_stop(struct usb_hcd *hcd)
{
}

/*
 * Context: unknown
 */
static void oz_hcd_shutdown(struct usb_hcd *hcd)
{
}

/*
 * Called to queue an urb for the device.
 * This function should return a non-zero error code if it fails the urb but
 * should not call usb_hcd_giveback_urb().
 * Context: any
 */
static int oz_hcd_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
				gfp_t mem_flags)
{
	struct oz_hcd *ozhcd = oz_hcd_private(hcd);
	int rc;
	int port_ix;
	struct oz_port *port;
	unsigned long irq_state;
	struct oz_urb_link *urbl;

	oz_dbg(URB, "%s: (%p)\n",  __func__, urb);
	if (unlikely(ozhcd == NULL)) {
		oz_dbg(URB, "Refused urb(%p) not ozhcd\n", urb);
		return -EPIPE;
	}
	if (unlikely(hcd->state != HC_STATE_RUNNING)) {
		oz_dbg(URB, "Refused urb(%p) not running\n", urb);
		return -EPIPE;
	}
	port_ix = oz_get_port_from_addr(ozhcd, urb->dev->devnum);
	if (port_ix < 0)
		return -EPIPE;
	port =  &ozhcd->ports[port_ix];
	if (port == NULL)
		return -EPIPE;
	if (!(port->flags & OZ_PORT_F_PRESENT) ||
				(port->flags & OZ_PORT_F_CHANGED)) {
		oz_dbg(ON, "Refusing URB port_ix = %d devnum = %d\n",
		       port_ix, urb->dev->devnum);
		return -EPIPE;
	}
	urb->hcpriv = port;
	/* Put request in queue for processing by tasklet.
	 */
	urbl = oz_alloc_urb_link();
	if (unlikely(urbl == NULL))
		return -ENOMEM;
	urbl->urb = urb;
	spin_lock_irqsave(&g_tasklet_lock, irq_state);
	rc = usb_hcd_link_urb_to_ep(hcd, urb);
	if (unlikely(rc)) {
		spin_unlock_irqrestore(&g_tasklet_lock, irq_state);
		oz_free_urb_link(urbl);
		return rc;
	}
	list_add_tail(&urbl->link, &ozhcd->urb_pending_list);
	spin_unlock_irqrestore(&g_tasklet_lock, irq_state);
	tasklet_schedule(&g_urb_process_tasklet);
	atomic_inc(&g_pending_urbs);
	return 0;
}

/*
 * Context: tasklet
 */
static struct oz_urb_link *oz_remove_urb(struct oz_endpoint *ep,
				struct urb *urb)
{
	struct oz_urb_link *urbl;
	struct list_head *e;

	if (unlikely(ep == NULL))
		return NULL;
	list_for_each(e, &ep->urb_list) {
		urbl = container_of(e, struct oz_urb_link, link);
		if (urbl->urb == urb) {
			list_del_init(e);
			if (usb_pipeisoc(urb->pipe)) {
				ep->credit -= urb->number_of_packets;
				if (ep->credit < 0)
					ep->credit = 0;
			}
			return urbl;
		}
	}
	return NULL;
}

/*
 * Called to dequeue a previously submitted urb for the device.
 * Context: any
 */
static int oz_hcd_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
{
	struct oz_hcd *ozhcd = oz_hcd_private(hcd);
	struct oz_urb_link *urbl;
	int rc;
	unsigned long irq_state;

	oz_dbg(URB, "%s: (%p)\n",  __func__, urb);
	urbl = oz_alloc_urb_link();
	if (unlikely(urbl == NULL))
		return -ENOMEM;
	spin_lock_irqsave(&g_tasklet_lock, irq_state);
	/* The following function checks the urb is still in the queue
	 * maintained by the core and that the unlinked field is zero.
	 * If both are true the function sets the unlinked field and returns
	 * zero. Otherwise it returns an error.
	 */
	rc = usb_hcd_check_unlink_urb(hcd, urb, status);
	/* We have to check we haven't completed the urb or are about
	 * to complete it. When we do we set hcpriv to 0 so if this has
	 * already happened we don't put the urb in the cancel queue.
	 */
	if ((rc == 0) && urb->hcpriv) {
		urbl->urb = urb;
		urbl->port = (struct oz_port *)urb->hcpriv;
		urbl->ep_num = usb_pipeendpoint(urb->pipe);
		if (usb_pipein(urb->pipe))
			urbl->ep_num |= USB_DIR_IN;
		list_add_tail(&urbl->link, &ozhcd->urb_cancel_list);
		spin_unlock_irqrestore(&g_tasklet_lock, irq_state);
		tasklet_schedule(&g_urb_cancel_tasklet);
	} else {
		spin_unlock_irqrestore(&g_tasklet_lock, irq_state);
		oz_free_urb_link(urbl);
	}
	return rc;
}

/*
 * Context: unknown
 */
static void oz_hcd_endpoint_disable(struct usb_hcd *hcd,
				struct usb_host_endpoint *ep)
{
}

/*
 * Context: unknown
 */
static void oz_hcd_endpoint_reset(struct usb_hcd *hcd,
				struct usb_host_endpoint *ep)
{
}

/*
 * Context: unknown
 */
static int oz_hcd_get_frame_number(struct usb_hcd *hcd)
{
	oz_dbg(ON, "oz_hcd_get_frame_number\n");
	return oz_usb_get_frame_number();
}

/*
 * Context: softirq
 * This is called as a consquence of us calling usb_hcd_poll_rh_status() and we
 * always do that in softirq context.
 */
static int oz_hcd_hub_status_data(struct usb_hcd *hcd, char *buf)
{
	struct oz_hcd *ozhcd = oz_hcd_private(hcd);
	int i;

	buf[0] = 0;
	buf[1] = 0;

	spin_lock_bh(&ozhcd->hcd_lock);
	for (i = 0; i < OZ_NB_PORTS; i++) {
		if (ozhcd->ports[i].flags & OZ_PORT_F_CHANGED) {
			oz_dbg(HUB, "Port %d changed\n", i);
			ozhcd->ports[i].flags &= ~OZ_PORT_F_CHANGED;
			if (i < 7)
				buf[0] |= 1 << (i + 1);
			else
				buf[1] |= 1 << (i - 7);
		}
	}
	spin_unlock_bh(&ozhcd->hcd_lock);
	if (buf[0] != 0 || buf[1] != 0)
		return 2;
	else
		return 0;
}

/*
 * Context: process
 */
static void oz_get_hub_descriptor(struct usb_hcd *hcd,
				struct usb_hub_descriptor *desc)
{
	memset(desc, 0, sizeof(*desc));
	desc->bDescriptorType = 0x29;
	desc->bDescLength = 9;
	desc->wHubCharacteristics = (__force __u16)
			__constant_cpu_to_le16(0x0001);
	desc->bNbrPorts = OZ_NB_PORTS;
}

/*
 * Context: process
 */
static int oz_set_port_feature(struct usb_hcd *hcd, u16 wvalue, u16 windex)
{
	struct oz_port *port;
	int err = 0;
	u8 port_id = (u8)windex;
	struct oz_hcd *ozhcd = oz_hcd_private(hcd);
	unsigned set_bits = 0;
	unsigned clear_bits = 0;

	if ((port_id < 1) || (port_id > OZ_NB_PORTS))
		return -EPIPE;
	port = &ozhcd->ports[port_id-1];
	switch (wvalue) {
	case USB_PORT_FEAT_CONNECTION:
		oz_dbg(HUB, "USB_PORT_FEAT_CONNECTION\n");
		break;
	case USB_PORT_FEAT_ENABLE:
		oz_dbg(HUB, "USB_PORT_FEAT_ENABLE\n");
		break;
	case USB_PORT_FEAT_SUSPEND:
		oz_dbg(HUB, "USB_PORT_FEAT_SUSPEND\n");
		break;
	case USB_PORT_FEAT_OVER_CURRENT:
		oz_dbg(HUB, "USB_PORT_FEAT_OVER_CURRENT\n");
		break;
	case USB_PORT_FEAT_RESET:
		oz_dbg(HUB, "USB_PORT_FEAT_RESET\n");
		set_bits = USB_PORT_STAT_ENABLE | (USB_PORT_STAT_C_RESET<<16);
		clear_bits = USB_PORT_STAT_RESET;
		ozhcd->ports[port_id-1].bus_addr = 0;
		break;
	case USB_PORT_FEAT_POWER:
		oz_dbg(HUB, "USB_PORT_FEAT_POWER\n");
		set_bits |= USB_PORT_STAT_POWER;
		break;
	case USB_PORT_FEAT_LOWSPEED:
		oz_dbg(HUB, "USB_PORT_FEAT_LOWSPEED\n");
		break;
	case USB_PORT_FEAT_C_CONNECTION:
		oz_dbg(HUB, "USB_PORT_FEAT_C_CONNECTION\n");
		break;
	case USB_PORT_FEAT_C_ENABLE:
		oz_dbg(HUB, "USB_PORT_FEAT_C_ENABLE\n");
		break;
	case USB_PORT_FEAT_C_SUSPEND:
		oz_dbg(HUB, "USB_PORT_FEAT_C_SUSPEND\n");
		break;
	case USB_PORT_FEAT_C_OVER_CURRENT:
		oz_dbg(HUB, "USB_PORT_FEAT_C_OVER_CURRENT\n");
		break;
	case USB_PORT_FEAT_C_RESET:
		oz_dbg(HUB, "USB_PORT_FEAT_C_RESET\n");
		break;
	case USB_PORT_FEAT_TEST:
		oz_dbg(HUB, "USB_PORT_FEAT_TEST\n");
		break;
	case USB_PORT_FEAT_INDICATOR:
		oz_dbg(HUB, "USB_PORT_FEAT_INDICATOR\n");
		break;
	default:
		oz_dbg(HUB, "Other %d\n", wvalue);
		break;
	}
	if (set_bits || clear_bits) {
		spin_lock_bh(&port->port_lock);
		port->status &= ~clear_bits;
		port->status |= set_bits;
		spin_unlock_bh(&port->port_lock);
	}
	oz_dbg(HUB, "Port[%d] status = 0x%x\n", port_id, port->status);
	return err;
}

/*
 * Context: process
 */
static int oz_clear_port_feature(struct usb_hcd *hcd, u16 wvalue, u16 windex)
{
	struct oz_port *port;
	int err = 0;
	u8 port_id = (u8)windex;
	struct oz_hcd *ozhcd = oz_hcd_private(hcd);
	unsigned clear_bits = 0;

	if ((port_id < 1) || (port_id > OZ_NB_PORTS))
		return -EPIPE;
	port = &ozhcd->ports[port_id-1];
	switch (wvalue) {
	case USB_PORT_FEAT_CONNECTION:
		oz_dbg(HUB, "USB_PORT_FEAT_CONNECTION\n");
		break;
	case USB_PORT_FEAT_ENABLE:
		oz_dbg(HUB, "USB_PORT_FEAT_ENABLE\n");
		clear_bits = USB_PORT_STAT_ENABLE;
		break;
	case USB_PORT_FEAT_SUSPEND:
		oz_dbg(HUB, "USB_PORT_FEAT_SUSPEND\n");
		break;
	case USB_PORT_FEAT_OVER_CURRENT:
		oz_dbg(HUB, "USB_PORT_FEAT_OVER_CURRENT\n");
		break;
	case USB_PORT_FEAT_RESET:
		oz_dbg(HUB, "USB_PORT_FEAT_RESET\n");
		break;
	case USB_PORT_FEAT_POWER:
		oz_dbg(HUB, "USB_PORT_FEAT_POWER\n");
		clear_bits |= USB_PORT_STAT_POWER;
		break;
	case USB_PORT_FEAT_LOWSPEED:
		oz_dbg(HUB, "USB_PORT_FEAT_LOWSPEED\n");
		break;
	case USB_PORT_FEAT_C_CONNECTION:
		oz_dbg(HUB, "USB_PORT_FEAT_C_CONNECTION\n");
		clear_bits = (USB_PORT_STAT_C_CONNECTION << 16);
		break;
	case USB_PORT_FEAT_C_ENABLE:
		oz_dbg(HUB, "USB_PORT_FEAT_C_ENABLE\n");
		clear_bits = (USB_PORT_STAT_C_ENABLE << 16);
		break;
	case USB_PORT_FEAT_C_SUSPEND:
		oz_dbg(HUB, "USB_PORT_FEAT_C_SUSPEND\n");
		break;
	case USB_PORT_FEAT_C_OVER_CURRENT:
		oz_dbg(HUB, "USB_PORT_FEAT_C_OVER_CURRENT\n");
		break;
	case USB_PORT_FEAT_C_RESET:
		oz_dbg(HUB, "USB_PORT_FEAT_C_RESET\n");
		clear_bits = (USB_PORT_FEAT_C_RESET << 16);
		break;
	case USB_PORT_FEAT_TEST:
		oz_dbg(HUB, "USB_PORT_FEAT_TEST\n");
		break;
	case USB_PORT_FEAT_INDICATOR:
		oz_dbg(HUB, "USB_PORT_FEAT_INDICATOR\n");
		break;
	default:
		oz_dbg(HUB, "Other %d\n", wvalue);
		break;
	}
	if (clear_bits) {
		spin_lock_bh(&port->port_lock);
		port->status &= ~clear_bits;
		spin_unlock_bh(&port->port_lock);
	}
	oz_dbg(HUB, "Port[%d] status = 0x%x\n",
	       port_id, ozhcd->ports[port_id-1].status);
	return err;
}

/*
 * Context: process
 */
static int oz_get_port_status(struct usb_hcd *hcd, u16 windex, char *buf)
{
	struct oz_hcd *ozhcd;
	u32 status;

	if ((windex < 1) || (windex > OZ_NB_PORTS))
		return -EPIPE;
	ozhcd = oz_hcd_private(hcd);
	oz_dbg(HUB, "GetPortStatus windex = %d\n", windex);
	status = ozhcd->ports[windex-1].status;
	put_unaligned(cpu_to_le32(status), (__le32 *)buf);
	oz_dbg(HUB, "Port[%d] status = %x\n", windex, status);
	return 0;
}

/*
 * Context: process
 */
static int oz_hcd_hub_control(struct usb_hcd *hcd, u16 req_type, u16 wvalue,
				u16 windex, char *buf, u16 wlength)
{
	int err = 0;

	switch (req_type) {
	case ClearHubFeature:
		oz_dbg(HUB, "ClearHubFeature: %d\n", req_type);
		break;
	case ClearPortFeature:
		err = oz_clear_port_feature(hcd, wvalue, windex);
		break;
	case GetHubDescriptor:
		oz_get_hub_descriptor(hcd, (struct usb_hub_descriptor *)buf);
		break;
	case GetHubStatus:
		oz_dbg(HUB, "GetHubStatus: req_type = 0x%x\n", req_type);
		put_unaligned(__constant_cpu_to_le32(0), (__le32 *)buf);
		break;
	case GetPortStatus:
		err = oz_get_port_status(hcd, windex, buf);
		break;
	case SetHubFeature:
		oz_dbg(HUB, "SetHubFeature: %d\n", req_type);
		break;
	case SetPortFeature:
		err = oz_set_port_feature(hcd, wvalue, windex);
		break;
	default:
		oz_dbg(HUB, "Other: %d\n", req_type);
		break;
	}
	return err;
}

/*
 * Context: process
 */
static int oz_hcd_bus_suspend(struct usb_hcd *hcd)
{
	struct oz_hcd *ozhcd;

	ozhcd = oz_hcd_private(hcd);
	spin_lock_bh(&ozhcd->hcd_lock);
	hcd->state = HC_STATE_SUSPENDED;
	ozhcd->flags |= OZ_HDC_F_SUSPENDED;
	spin_unlock_bh(&ozhcd->hcd_lock);
	return 0;
}

/*
 * Context: process
 */
static int oz_hcd_bus_resume(struct usb_hcd *hcd)
{
	struct oz_hcd *ozhcd;

	ozhcd = oz_hcd_private(hcd);
	spin_lock_bh(&ozhcd->hcd_lock);
	ozhcd->flags &= ~OZ_HDC_F_SUSPENDED;
	hcd->state = HC_STATE_RUNNING;
	spin_unlock_bh(&ozhcd->hcd_lock);
	return 0;
}

static void oz_plat_shutdown(struct platform_device *dev)
{
}

/*
 * Context: process
 */
static int oz_plat_probe(struct platform_device *dev)
{
	int i;
	int err;
	struct usb_hcd *hcd;
	struct oz_hcd *ozhcd;

	hcd = usb_create_hcd(&g_oz_hc_drv, &dev->dev, dev_name(&dev->dev));
	if (hcd == NULL) {
		oz_dbg(ON, "Failed to created hcd object OK\n");
		return -ENOMEM;
	}
	ozhcd = oz_hcd_private(hcd);
	memset(ozhcd, 0, sizeof(*ozhcd));
	INIT_LIST_HEAD(&ozhcd->urb_pending_list);
	INIT_LIST_HEAD(&ozhcd->urb_cancel_list);
	INIT_LIST_HEAD(&ozhcd->orphanage);
	ozhcd->hcd = hcd;
	ozhcd->conn_port = -1;
	spin_lock_init(&ozhcd->hcd_lock);
	for (i = 0; i < OZ_NB_PORTS; i++) {
		struct oz_port *port = &ozhcd->ports[i];
		port->ozhcd = ozhcd;
		port->flags = 0;
		port->status = 0;
		port->bus_addr = 0xff;
		spin_lock_init(&port->port_lock);
	}
	err = usb_add_hcd(hcd, 0, 0);
	if (err) {
		oz_dbg(ON, "Failed to add hcd object OK\n");
		usb_put_hcd(hcd);
		return -1;
	}
	spin_lock_bh(&g_hcdlock);
	g_ozhcd = ozhcd;
	spin_unlock_bh(&g_hcdlock);
	return 0;
}

/*
 * Context: unknown
 */
static int oz_plat_remove(struct platform_device *dev)
{
	struct usb_hcd *hcd = platform_get_drvdata(dev);
	struct oz_hcd *ozhcd;

	if (hcd == NULL)
		return -1;
	ozhcd = oz_hcd_private(hcd);
	spin_lock_bh(&g_hcdlock);
	if (ozhcd == g_ozhcd)
		g_ozhcd = NULL;
	spin_unlock_bh(&g_hcdlock);
	oz_dbg(ON, "Clearing orphanage\n");
	oz_hcd_clear_orphanage(ozhcd, -EPIPE);
	oz_dbg(ON, "Removing hcd\n");
	usb_remove_hcd(hcd);
	usb_put_hcd(hcd);
	oz_empty_link_pool();
	return 0;
}

/*
 * Context: unknown
 */
static int oz_plat_suspend(struct platform_device *dev, pm_message_t msg)
{
	return 0;
}


/*
 * Context: unknown
 */
static int oz_plat_resume(struct platform_device *dev)
{
	return 0;
}

/*
 * Context: process
 */
int oz_hcd_init(void)
{
	int err;

	if (usb_disabled())
		return -ENODEV;
	tasklet_init(&g_urb_process_tasklet, oz_urb_process_tasklet, 0);
	tasklet_init(&g_urb_cancel_tasklet, oz_urb_cancel_tasklet, 0);
	err = platform_driver_register(&g_oz_plat_drv);
	oz_dbg(ON, "platform_driver_register() returned %d\n", err);
	if (err)
		goto error;
	g_plat_dev = platform_device_alloc(OZ_PLAT_DEV_NAME, -1);
	if (g_plat_dev == NULL) {
		err = -ENOMEM;
		goto error1;
	}
	oz_dbg(ON, "platform_device_alloc() succeeded\n");
	err = platform_device_add(g_plat_dev);
	if (err)
		goto error2;
	oz_dbg(ON, "platform_device_add() succeeded\n");
	return 0;
error2:
	platform_device_put(g_plat_dev);
error1:
	platform_driver_unregister(&g_oz_plat_drv);
error:
	tasklet_disable(&g_urb_process_tasklet);
	tasklet_disable(&g_urb_cancel_tasklet);
	oz_dbg(ON, "oz_hcd_init() failed %d\n", err);
	return err;
}

/*
 * Context: process
 */
void oz_hcd_term(void)
{
	msleep(OZ_HUB_DEBOUNCE_TIMEOUT);
	tasklet_kill(&g_urb_process_tasklet);
	tasklet_kill(&g_urb_cancel_tasklet);
	platform_device_unregister(g_plat_dev);
	platform_driver_unregister(&g_oz_plat_drv);
	oz_dbg(ON, "Pending urbs:%d\n", atomic_read(&g_pending_urbs));
}