Linux Audio

Check our new training course

Embedded Linux Audio

Check our new training course
with Creative Commons CC-BY-SA
lecture materials

Bootlin logo

Elixir Cross Referencer

Loading...
   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
/*
 * Enhanced Host Controller Interface (EHCI) driver for USB.
 *
 * Maintainer: Alan Stern <stern@rowland.harvard.edu>
 *
 * Copyright (c) 2000-2004 by David Brownell
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2 of the License, or (at your
 * option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/module.h>
#include <linux/pci.h>
#include <linux/dmapool.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/ioport.h>
#include <linux/sched.h>
#include <linux/vmalloc.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/hrtimer.h>
#include <linux/list.h>
#include <linux/interrupt.h>
#include <linux/usb.h>
#include <linux/usb/hcd.h>
#include <linux/moduleparam.h>
#include <linux/dma-mapping.h>
#include <linux/debugfs.h>
#include <linux/slab.h>

#include <asm/byteorder.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/unaligned.h>

#if defined(CONFIG_PPC_PS3)
#include <asm/firmware.h>
#endif

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

/*
 * EHCI hc_driver implementation ... experimental, incomplete.
 * Based on the final 1.0 register interface specification.
 *
 * USB 2.0 shows up in upcoming www.pcmcia.org technology.
 * First was PCMCIA, like ISA; then CardBus, which is PCI.
 * Next comes "CardBay", using USB 2.0 signals.
 *
 * Contains additional contributions by Brad Hards, Rory Bolt, and others.
 * Special thanks to Intel and VIA for providing host controllers to
 * test this driver on, and Cypress (including In-System Design) for
 * providing early devices for those host controllers to talk to!
 */

#define DRIVER_AUTHOR "David Brownell"
#define DRIVER_DESC "USB 2.0 'Enhanced' Host Controller (EHCI) Driver"

static const char	hcd_name [] = "ehci_hcd";


#undef EHCI_URB_TRACE

/* magic numbers that can affect system performance */
#define	EHCI_TUNE_CERR		3	/* 0-3 qtd retries; 0 == don't stop */
#define	EHCI_TUNE_RL_HS		4	/* nak throttle; see 4.9 */
#define	EHCI_TUNE_RL_TT		0
#define	EHCI_TUNE_MULT_HS	1	/* 1-3 transactions/uframe; 4.10.3 */
#define	EHCI_TUNE_MULT_TT	1
/*
 * Some drivers think it's safe to schedule isochronous transfers more than
 * 256 ms into the future (partly as a result of an old bug in the scheduling
 * code).  In an attempt to avoid trouble, we will use a minimum scheduling
 * length of 512 frames instead of 256.
 */
#define	EHCI_TUNE_FLS		1	/* (medium) 512-frame schedule */

/* Initial IRQ latency:  faster than hw default */
static int log2_irq_thresh = 0;		// 0 to 6
module_param (log2_irq_thresh, int, S_IRUGO);
MODULE_PARM_DESC (log2_irq_thresh, "log2 IRQ latency, 1-64 microframes");

/* initial park setting:  slower than hw default */
static unsigned park = 0;
module_param (park, uint, S_IRUGO);
MODULE_PARM_DESC (park, "park setting; 1-3 back-to-back async packets");

/* for flakey hardware, ignore overcurrent indicators */
static bool ignore_oc = 0;
module_param (ignore_oc, bool, S_IRUGO);
MODULE_PARM_DESC (ignore_oc, "ignore bogus hardware overcurrent indications");

#define	INTR_MASK (STS_IAA | STS_FATAL | STS_PCD | STS_ERR | STS_INT)

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

#include "ehci.h"
#include "pci-quirks.h"

static void compute_tt_budget(u8 budget_table[EHCI_BANDWIDTH_SIZE],
		struct ehci_tt *tt);

/*
 * The MosChip MCS9990 controller updates its microframe counter
 * a little before the frame counter, and occasionally we will read
 * the invalid intermediate value.  Avoid problems by checking the
 * microframe number (the low-order 3 bits); if they are 0 then
 * re-read the register to get the correct value.
 */
static unsigned ehci_moschip_read_frame_index(struct ehci_hcd *ehci)
{
	unsigned uf;

	uf = ehci_readl(ehci, &ehci->regs->frame_index);
	if (unlikely((uf & 7) == 0))
		uf = ehci_readl(ehci, &ehci->regs->frame_index);
	return uf;
}

static inline unsigned ehci_read_frame_index(struct ehci_hcd *ehci)
{
	if (ehci->frame_index_bug)
		return ehci_moschip_read_frame_index(ehci);
	return ehci_readl(ehci, &ehci->regs->frame_index);
}

#include "ehci-dbg.c"

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

/*
 * ehci_handshake - spin reading hc until handshake completes or fails
 * @ptr: address of hc register to be read
 * @mask: bits to look at in result of read
 * @done: value of those bits when handshake succeeds
 * @usec: timeout in microseconds
 *
 * Returns negative errno, or zero on success
 *
 * Success happens when the "mask" bits have the specified value (hardware
 * handshake done).  There are two failure modes:  "usec" have passed (major
 * hardware flakeout), or the register reads as all-ones (hardware removed).
 *
 * That last failure should_only happen in cases like physical cardbus eject
 * before driver shutdown. But it also seems to be caused by bugs in cardbus
 * bridge shutdown:  shutting down the bridge before the devices using it.
 */
int ehci_handshake(struct ehci_hcd *ehci, void __iomem *ptr,
		   u32 mask, u32 done, int usec)
{
	u32	result;

	do {
		result = ehci_readl(ehci, ptr);
		if (result == ~(u32)0)		/* card removed */
			return -ENODEV;
		result &= mask;
		if (result == done)
			return 0;
		udelay (1);
		usec--;
	} while (usec > 0);
	return -ETIMEDOUT;
}
EXPORT_SYMBOL_GPL(ehci_handshake);

/* check TDI/ARC silicon is in host mode */
static int tdi_in_host_mode (struct ehci_hcd *ehci)
{
	u32		tmp;

	tmp = ehci_readl(ehci, &ehci->regs->usbmode);
	return (tmp & 3) == USBMODE_CM_HC;
}

/*
 * Force HC to halt state from unknown (EHCI spec section 2.3).
 * Must be called with interrupts enabled and the lock not held.
 */
static int ehci_halt (struct ehci_hcd *ehci)
{
	u32	temp;

	spin_lock_irq(&ehci->lock);

	/* disable any irqs left enabled by previous code */
	ehci_writel(ehci, 0, &ehci->regs->intr_enable);

	if (ehci_is_TDI(ehci) && !tdi_in_host_mode(ehci)) {
		spin_unlock_irq(&ehci->lock);
		return 0;
	}

	/*
	 * This routine gets called during probe before ehci->command
	 * has been initialized, so we can't rely on its value.
	 */
	ehci->command &= ~CMD_RUN;
	temp = ehci_readl(ehci, &ehci->regs->command);
	temp &= ~(CMD_RUN | CMD_IAAD);
	ehci_writel(ehci, temp, &ehci->regs->command);

	spin_unlock_irq(&ehci->lock);
	synchronize_irq(ehci_to_hcd(ehci)->irq);

	return ehci_handshake(ehci, &ehci->regs->status,
			  STS_HALT, STS_HALT, 16 * 125);
}

/* put TDI/ARC silicon into EHCI mode */
static void tdi_reset (struct ehci_hcd *ehci)
{
	u32		tmp;

	tmp = ehci_readl(ehci, &ehci->regs->usbmode);
	tmp |= USBMODE_CM_HC;
	/* The default byte access to MMR space is LE after
	 * controller reset. Set the required endian mode
	 * for transfer buffers to match the host microprocessor
	 */
	if (ehci_big_endian_mmio(ehci))
		tmp |= USBMODE_BE;
	ehci_writel(ehci, tmp, &ehci->regs->usbmode);
}

/*
 * Reset a non-running (STS_HALT == 1) controller.
 * Must be called with interrupts enabled and the lock not held.
 */
int ehci_reset(struct ehci_hcd *ehci)
{
	int	retval;
	u32	command = ehci_readl(ehci, &ehci->regs->command);

	/* If the EHCI debug controller is active, special care must be
	 * taken before and after a host controller reset */
	if (ehci->debug && !dbgp_reset_prep(ehci_to_hcd(ehci)))
		ehci->debug = NULL;

	command |= CMD_RESET;
	dbg_cmd (ehci, "reset", command);
	ehci_writel(ehci, command, &ehci->regs->command);
	ehci->rh_state = EHCI_RH_HALTED;
	ehci->next_statechange = jiffies;
	retval = ehci_handshake(ehci, &ehci->regs->command,
			    CMD_RESET, 0, 250 * 1000);

	if (ehci->has_hostpc) {
		ehci_writel(ehci, USBMODE_EX_HC | USBMODE_EX_VBPS,
				&ehci->regs->usbmode_ex);
		ehci_writel(ehci, TXFIFO_DEFAULT, &ehci->regs->txfill_tuning);
	}
	if (retval)
		return retval;

	if (ehci_is_TDI(ehci))
		tdi_reset (ehci);

	if (ehci->debug)
		dbgp_external_startup(ehci_to_hcd(ehci));

	ehci->port_c_suspend = ehci->suspended_ports =
			ehci->resuming_ports = 0;
	return retval;
}
EXPORT_SYMBOL_GPL(ehci_reset);

/*
 * Idle the controller (turn off the schedules).
 * Must be called with interrupts enabled and the lock not held.
 */
static void ehci_quiesce (struct ehci_hcd *ehci)
{
	u32	temp;

	if (ehci->rh_state != EHCI_RH_RUNNING)
		return;

	/* wait for any schedule enables/disables to take effect */
	temp = (ehci->command << 10) & (STS_ASS | STS_PSS);
	ehci_handshake(ehci, &ehci->regs->status, STS_ASS | STS_PSS, temp,
			16 * 125);

	/* then disable anything that's still active */
	spin_lock_irq(&ehci->lock);
	ehci->command &= ~(CMD_ASE | CMD_PSE);
	ehci_writel(ehci, ehci->command, &ehci->regs->command);
	spin_unlock_irq(&ehci->lock);

	/* hardware can take 16 microframes to turn off ... */
	ehci_handshake(ehci, &ehci->regs->status, STS_ASS | STS_PSS, 0,
			16 * 125);
}

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

static void end_unlink_async(struct ehci_hcd *ehci);
static void unlink_empty_async(struct ehci_hcd *ehci);
static void unlink_empty_async_suspended(struct ehci_hcd *ehci);
static void ehci_work(struct ehci_hcd *ehci);
static void start_unlink_intr(struct ehci_hcd *ehci, struct ehci_qh *qh);
static void end_unlink_intr(struct ehci_hcd *ehci, struct ehci_qh *qh);
static int ehci_port_power(struct ehci_hcd *ehci, int portnum, bool enable);

#include "ehci-timer.c"
#include "ehci-hub.c"
#include "ehci-mem.c"
#include "ehci-q.c"
#include "ehci-sched.c"
#include "ehci-sysfs.c"

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

/* On some systems, leaving remote wakeup enabled prevents system shutdown.
 * The firmware seems to think that powering off is a wakeup event!
 * This routine turns off remote wakeup and everything else, on all ports.
 */
static void ehci_turn_off_all_ports(struct ehci_hcd *ehci)
{
	int	port = HCS_N_PORTS(ehci->hcs_params);

	while (port--) {
		spin_unlock_irq(&ehci->lock);
		ehci_port_power(ehci, port, false);
		spin_lock_irq(&ehci->lock);
		ehci_writel(ehci, PORT_RWC_BITS,
				&ehci->regs->port_status[port]);
	}
}

/*
 * Halt HC, turn off all ports, and let the BIOS use the companion controllers.
 * Must be called with interrupts enabled and the lock not held.
 */
static void ehci_silence_controller(struct ehci_hcd *ehci)
{
	ehci_halt(ehci);

	spin_lock_irq(&ehci->lock);
	ehci->rh_state = EHCI_RH_HALTED;
	ehci_turn_off_all_ports(ehci);

	/* make BIOS/etc use companion controller during reboot */
	ehci_writel(ehci, 0, &ehci->regs->configured_flag);

	/* unblock posted writes */
	ehci_readl(ehci, &ehci->regs->configured_flag);
	spin_unlock_irq(&ehci->lock);
}

/* ehci_shutdown kick in for silicon on any bus (not just pci, etc).
 * This forcibly disables dma and IRQs, helping kexec and other cases
 * where the next system software may expect clean state.
 */
static void ehci_shutdown(struct usb_hcd *hcd)
{
	struct ehci_hcd	*ehci = hcd_to_ehci(hcd);

	spin_lock_irq(&ehci->lock);
	ehci->shutdown = true;
	ehci->rh_state = EHCI_RH_STOPPING;
	ehci->enabled_hrtimer_events = 0;
	spin_unlock_irq(&ehci->lock);

	ehci_silence_controller(ehci);

	hrtimer_cancel(&ehci->hrtimer);
}

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

/*
 * ehci_work is called from some interrupts, timers, and so on.
 * it calls driver completion functions, after dropping ehci->lock.
 */
static void ehci_work (struct ehci_hcd *ehci)
{
	/* another CPU may drop ehci->lock during a schedule scan while
	 * it reports urb completions.  this flag guards against bogus
	 * attempts at re-entrant schedule scanning.
	 */
	if (ehci->scanning) {
		ehci->need_rescan = true;
		return;
	}
	ehci->scanning = true;

 rescan:
	ehci->need_rescan = false;
	if (ehci->async_count)
		scan_async(ehci);
	if (ehci->intr_count > 0)
		scan_intr(ehci);
	if (ehci->isoc_count > 0)
		scan_isoc(ehci);
	if (ehci->need_rescan)
		goto rescan;
	ehci->scanning = false;

	/* the IO watchdog guards against hardware or driver bugs that
	 * misplace IRQs, and should let us run completely without IRQs.
	 * such lossage has been observed on both VT6202 and VT8235.
	 */
	turn_on_io_watchdog(ehci);
}

/*
 * Called when the ehci_hcd module is removed.
 */
static void ehci_stop (struct usb_hcd *hcd)
{
	struct ehci_hcd		*ehci = hcd_to_ehci (hcd);

	ehci_dbg (ehci, "stop\n");

	/* no more interrupts ... */

	spin_lock_irq(&ehci->lock);
	ehci->enabled_hrtimer_events = 0;
	spin_unlock_irq(&ehci->lock);

	ehci_quiesce(ehci);
	ehci_silence_controller(ehci);
	ehci_reset (ehci);

	hrtimer_cancel(&ehci->hrtimer);
	remove_sysfs_files(ehci);
	remove_debug_files (ehci);

	/* root hub is shut down separately (first, when possible) */
	spin_lock_irq (&ehci->lock);
	end_free_itds(ehci);
	spin_unlock_irq (&ehci->lock);
	ehci_mem_cleanup (ehci);

	if (ehci->amd_pll_fix == 1)
		usb_amd_dev_put();

	dbg_status (ehci, "ehci_stop completed",
		    ehci_readl(ehci, &ehci->regs->status));
}

/* one-time init, only for memory state */
static int ehci_init(struct usb_hcd *hcd)
{
	struct ehci_hcd		*ehci = hcd_to_ehci(hcd);
	u32			temp;
	int			retval;
	u32			hcc_params;
	struct ehci_qh_hw	*hw;

	spin_lock_init(&ehci->lock);

	/*
	 * keep io watchdog by default, those good HCDs could turn off it later
	 */
	ehci->need_io_watchdog = 1;

	hrtimer_init(&ehci->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
	ehci->hrtimer.function = ehci_hrtimer_func;
	ehci->next_hrtimer_event = EHCI_HRTIMER_NO_EVENT;

	hcc_params = ehci_readl(ehci, &ehci->caps->hcc_params);

	/*
	 * by default set standard 80% (== 100 usec/uframe) max periodic
	 * bandwidth as required by USB 2.0
	 */
	ehci->uframe_periodic_max = 100;

	/*
	 * hw default: 1K periodic list heads, one per frame.
	 * periodic_size can shrink by USBCMD update if hcc_params allows.
	 */
	ehci->periodic_size = DEFAULT_I_TDPS;
	INIT_LIST_HEAD(&ehci->async_unlink);
	INIT_LIST_HEAD(&ehci->async_idle);
	INIT_LIST_HEAD(&ehci->intr_unlink_wait);
	INIT_LIST_HEAD(&ehci->intr_unlink);
	INIT_LIST_HEAD(&ehci->intr_qh_list);
	INIT_LIST_HEAD(&ehci->cached_itd_list);
	INIT_LIST_HEAD(&ehci->cached_sitd_list);
	INIT_LIST_HEAD(&ehci->tt_list);

	if (HCC_PGM_FRAMELISTLEN(hcc_params)) {
		/* periodic schedule size can be smaller than default */
		switch (EHCI_TUNE_FLS) {
		case 0: ehci->periodic_size = 1024; break;
		case 1: ehci->periodic_size = 512; break;
		case 2: ehci->periodic_size = 256; break;
		default:	BUG();
		}
	}
	if ((retval = ehci_mem_init(ehci, GFP_KERNEL)) < 0)
		return retval;

	/* controllers may cache some of the periodic schedule ... */
	if (HCC_ISOC_CACHE(hcc_params))		// full frame cache
		ehci->i_thresh = 0;
	else					// N microframes cached
		ehci->i_thresh = 2 + HCC_ISOC_THRES(hcc_params);

	/*
	 * dedicate a qh for the async ring head, since we couldn't unlink
	 * a 'real' qh without stopping the async schedule [4.8].  use it
	 * as the 'reclamation list head' too.
	 * its dummy is used in hw_alt_next of many tds, to prevent the qh
	 * from automatically advancing to the next td after short reads.
	 */
	ehci->async->qh_next.qh = NULL;
	hw = ehci->async->hw;
	hw->hw_next = QH_NEXT(ehci, ehci->async->qh_dma);
	hw->hw_info1 = cpu_to_hc32(ehci, QH_HEAD);
#if defined(CONFIG_PPC_PS3)
	hw->hw_info1 |= cpu_to_hc32(ehci, QH_INACTIVATE);
#endif
	hw->hw_token = cpu_to_hc32(ehci, QTD_STS_HALT);
	hw->hw_qtd_next = EHCI_LIST_END(ehci);
	ehci->async->qh_state = QH_STATE_LINKED;
	hw->hw_alt_next = QTD_NEXT(ehci, ehci->async->dummy->qtd_dma);

	/* clear interrupt enables, set irq latency */
	if (log2_irq_thresh < 0 || log2_irq_thresh > 6)
		log2_irq_thresh = 0;
	temp = 1 << (16 + log2_irq_thresh);
	if (HCC_PER_PORT_CHANGE_EVENT(hcc_params)) {
		ehci->has_ppcd = 1;
		ehci_dbg(ehci, "enable per-port change event\n");
		temp |= CMD_PPCEE;
	}
	if (HCC_CANPARK(hcc_params)) {
		/* HW default park == 3, on hardware that supports it (like
		 * NVidia and ALI silicon), maximizes throughput on the async
		 * schedule by avoiding QH fetches between transfers.
		 *
		 * With fast usb storage devices and NForce2, "park" seems to
		 * make problems:  throughput reduction (!), data errors...
		 */
		if (park) {
			park = min(park, (unsigned) 3);
			temp |= CMD_PARK;
			temp |= park << 8;
		}
		ehci_dbg(ehci, "park %d\n", park);
	}
	if (HCC_PGM_FRAMELISTLEN(hcc_params)) {
		/* periodic schedule size can be smaller than default */
		temp &= ~(3 << 2);
		temp |= (EHCI_TUNE_FLS << 2);
	}
	ehci->command = temp;

	/* Accept arbitrarily long scatter-gather lists */
	if (!(hcd->driver->flags & HCD_LOCAL_MEM))
		hcd->self.sg_tablesize = ~0;
	return 0;
}

/* start HC running; it's halted, ehci_init() has been run (once) */
static int ehci_run (struct usb_hcd *hcd)
{
	struct ehci_hcd		*ehci = hcd_to_ehci (hcd);
	u32			temp;
	u32			hcc_params;

	hcd->uses_new_polling = 1;

	/* EHCI spec section 4.1 */

	ehci_writel(ehci, ehci->periodic_dma, &ehci->regs->frame_list);
	ehci_writel(ehci, (u32)ehci->async->qh_dma, &ehci->regs->async_next);

	/*
	 * hcc_params controls whether ehci->regs->segment must (!!!)
	 * be used; it constrains QH/ITD/SITD and QTD locations.
	 * pci_pool consistent memory always uses segment zero.
	 * streaming mappings for I/O buffers, like pci_map_single(),
	 * can return segments above 4GB, if the device allows.
	 *
	 * NOTE:  the dma mask is visible through dev->dma_mask, so
	 * drivers can pass this info along ... like NETIF_F_HIGHDMA,
	 * Scsi_Host.highmem_io, and so forth.  It's readonly to all
	 * host side drivers though.
	 */
	hcc_params = ehci_readl(ehci, &ehci->caps->hcc_params);
	if (HCC_64BIT_ADDR(hcc_params)) {
		ehci_writel(ehci, 0, &ehci->regs->segment);
#if 0
// this is deeply broken on almost all architectures
		if (!dma_set_mask(hcd->self.controller, DMA_BIT_MASK(64)))
			ehci_info(ehci, "enabled 64bit DMA\n");
#endif
	}


	// Philips, Intel, and maybe others need CMD_RUN before the
	// root hub will detect new devices (why?); NEC doesn't
	ehci->command &= ~(CMD_LRESET|CMD_IAAD|CMD_PSE|CMD_ASE|CMD_RESET);
	ehci->command |= CMD_RUN;
	ehci_writel(ehci, ehci->command, &ehci->regs->command);
	dbg_cmd (ehci, "init", ehci->command);

	/*
	 * Start, enabling full USB 2.0 functionality ... usb 1.1 devices
	 * are explicitly handed to companion controller(s), so no TT is
	 * involved with the root hub.  (Except where one is integrated,
	 * and there's no companion controller unless maybe for USB OTG.)
	 *
	 * Turning on the CF flag will transfer ownership of all ports
	 * from the companions to the EHCI controller.  If any of the
	 * companions are in the middle of a port reset at the time, it
	 * could cause trouble.  Write-locking ehci_cf_port_reset_rwsem
	 * guarantees that no resets are in progress.  After we set CF,
	 * a short delay lets the hardware catch up; new resets shouldn't
	 * be started before the port switching actions could complete.
	 */
	down_write(&ehci_cf_port_reset_rwsem);
	ehci->rh_state = EHCI_RH_RUNNING;
	ehci_writel(ehci, FLAG_CF, &ehci->regs->configured_flag);
	ehci_readl(ehci, &ehci->regs->command);	/* unblock posted writes */
	msleep(5);
	up_write(&ehci_cf_port_reset_rwsem);
	ehci->last_periodic_enable = ktime_get_real();

	temp = HC_VERSION(ehci, ehci_readl(ehci, &ehci->caps->hc_capbase));
	ehci_info (ehci,
		"USB %x.%x started, EHCI %x.%02x%s\n",
		((ehci->sbrn & 0xf0)>>4), (ehci->sbrn & 0x0f),
		temp >> 8, temp & 0xff,
		ignore_oc ? ", overcurrent ignored" : "");

	ehci_writel(ehci, INTR_MASK,
		    &ehci->regs->intr_enable); /* Turn On Interrupts */

	/* GRR this is run-once init(), being done every time the HC starts.
	 * So long as they're part of class devices, we can't do it init()
	 * since the class device isn't created that early.
	 */
	create_debug_files(ehci);
	create_sysfs_files(ehci);

	return 0;
}

int ehci_setup(struct usb_hcd *hcd)
{
	struct ehci_hcd *ehci = hcd_to_ehci(hcd);
	int retval;

	ehci->regs = (void __iomem *)ehci->caps +
	    HC_LENGTH(ehci, ehci_readl(ehci, &ehci->caps->hc_capbase));
	dbg_hcs_params(ehci, "reset");
	dbg_hcc_params(ehci, "reset");

	/* cache this readonly data; minimize chip reads */
	ehci->hcs_params = ehci_readl(ehci, &ehci->caps->hcs_params);

	ehci->sbrn = HCD_USB2;

	/* data structure init */
	retval = ehci_init(hcd);
	if (retval)
		return retval;

	retval = ehci_halt(ehci);
	if (retval)
		return retval;

	ehci_reset(ehci);

	return 0;
}
EXPORT_SYMBOL_GPL(ehci_setup);

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

static irqreturn_t ehci_irq (struct usb_hcd *hcd)
{
	struct ehci_hcd		*ehci = hcd_to_ehci (hcd);
	u32			status, masked_status, pcd_status = 0, cmd;
	int			bh;
	unsigned long		flags;

	/*
	 * For threadirqs option we use spin_lock_irqsave() variant to prevent
	 * deadlock with ehci hrtimer callback, because hrtimer callbacks run
	 * in interrupt context even when threadirqs is specified. We can go
	 * back to spin_lock() variant when hrtimer callbacks become threaded.
	 */
	spin_lock_irqsave(&ehci->lock, flags);

	status = ehci_readl(ehci, &ehci->regs->status);

	/* e.g. cardbus physical eject */
	if (status == ~(u32) 0) {
		ehci_dbg (ehci, "device removed\n");
		goto dead;
	}

	/*
	 * We don't use STS_FLR, but some controllers don't like it to
	 * remain on, so mask it out along with the other status bits.
	 */
	masked_status = status & (INTR_MASK | STS_FLR);

	/* Shared IRQ? */
	if (!masked_status || unlikely(ehci->rh_state == EHCI_RH_HALTED)) {
		spin_unlock_irqrestore(&ehci->lock, flags);
		return IRQ_NONE;
	}

	/* clear (just) interrupts */
	ehci_writel(ehci, masked_status, &ehci->regs->status);
	cmd = ehci_readl(ehci, &ehci->regs->command);
	bh = 0;

	/* normal [4.15.1.2] or error [4.15.1.1] completion */
	if (likely ((status & (STS_INT|STS_ERR)) != 0)) {
		if (likely ((status & STS_ERR) == 0))
			COUNT (ehci->stats.normal);
		else
			COUNT (ehci->stats.error);
		bh = 1;
	}

	/* complete the unlinking of some qh [4.15.2.3] */
	if (status & STS_IAA) {

		/* Turn off the IAA watchdog */
		ehci->enabled_hrtimer_events &= ~BIT(EHCI_HRTIMER_IAA_WATCHDOG);

		/*
		 * Mild optimization: Allow another IAAD to reset the
		 * hrtimer, if one occurs before the next expiration.
		 * In theory we could always cancel the hrtimer, but
		 * tests show that about half the time it will be reset
		 * for some other event anyway.
		 */
		if (ehci->next_hrtimer_event == EHCI_HRTIMER_IAA_WATCHDOG)
			++ehci->next_hrtimer_event;

		/* guard against (alleged) silicon errata */
		if (cmd & CMD_IAAD)
			ehci_dbg(ehci, "IAA with IAAD still set?\n");
		if (ehci->iaa_in_progress)
			COUNT(ehci->stats.iaa);
		end_unlink_async(ehci);
	}

	/* remote wakeup [4.3.1] */
	if (status & STS_PCD) {
		unsigned	i = HCS_N_PORTS (ehci->hcs_params);
		u32		ppcd = ~0;

		/* kick root hub later */
		pcd_status = status;

		/* resume root hub? */
		if (ehci->rh_state == EHCI_RH_SUSPENDED)
			usb_hcd_resume_root_hub(hcd);

		/* get per-port change detect bits */
		if (ehci->has_ppcd)
			ppcd = status >> 16;

		while (i--) {
			int pstatus;

			/* leverage per-port change bits feature */
			if (!(ppcd & (1 << i)))
				continue;
			pstatus = ehci_readl(ehci,
					 &ehci->regs->port_status[i]);

			if (pstatus & PORT_OWNER)
				continue;
			if (!(test_bit(i, &ehci->suspended_ports) &&
					((pstatus & PORT_RESUME) ||
						!(pstatus & PORT_SUSPEND)) &&
					(pstatus & PORT_PE) &&
					ehci->reset_done[i] == 0))
				continue;

			/* start USB_RESUME_TIMEOUT msec resume signaling from
			 * this port, and make hub_wq collect
			 * PORT_STAT_C_SUSPEND to stop that signaling.
			 */
			ehci->reset_done[i] = jiffies +
				msecs_to_jiffies(USB_RESUME_TIMEOUT);
			set_bit(i, &ehci->resuming_ports);
			ehci_dbg (ehci, "port %d remote wakeup\n", i + 1);
			usb_hcd_start_port_resume(&hcd->self, i);
			mod_timer(&hcd->rh_timer, ehci->reset_done[i]);
		}
	}

	/* PCI errors [4.15.2.4] */
	if (unlikely ((status & STS_FATAL) != 0)) {
		ehci_err(ehci, "fatal error\n");
		dbg_cmd(ehci, "fatal", cmd);
		dbg_status(ehci, "fatal", status);
dead:
		usb_hc_died(hcd);

		/* Don't let the controller do anything more */
		ehci->shutdown = true;
		ehci->rh_state = EHCI_RH_STOPPING;
		ehci->command &= ~(CMD_RUN | CMD_ASE | CMD_PSE);
		ehci_writel(ehci, ehci->command, &ehci->regs->command);
		ehci_writel(ehci, 0, &ehci->regs->intr_enable);
		ehci_handle_controller_death(ehci);

		/* Handle completions when the controller stops */
		bh = 0;
	}

	if (bh)
		ehci_work (ehci);
	spin_unlock_irqrestore(&ehci->lock, flags);
	if (pcd_status)
		usb_hcd_poll_rh_status(hcd);
	return IRQ_HANDLED;
}

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

/*
 * non-error returns are a promise to giveback() the urb later
 * we drop ownership so next owner (or urb unlink) can get it
 *
 * urb + dev is in hcd.self.controller.urb_list
 * we're queueing TDs onto software and hardware lists
 *
 * hcd-specific init for hcpriv hasn't been done yet
 *
 * NOTE:  control, bulk, and interrupt share the same code to append TDs
 * to a (possibly active) QH, and the same QH scanning code.
 */
static int ehci_urb_enqueue (
	struct usb_hcd	*hcd,
	struct urb	*urb,
	gfp_t		mem_flags
) {
	struct ehci_hcd		*ehci = hcd_to_ehci (hcd);
	struct list_head	qtd_list;

	INIT_LIST_HEAD (&qtd_list);

	switch (usb_pipetype (urb->pipe)) {
	case PIPE_CONTROL:
		/* qh_completions() code doesn't handle all the fault cases
		 * in multi-TD control transfers.  Even 1KB is rare anyway.
		 */
		if (urb->transfer_buffer_length > (16 * 1024))
			return -EMSGSIZE;
		/* FALLTHROUGH */
	/* case PIPE_BULK: */
	default:
		if (!qh_urb_transaction (ehci, urb, &qtd_list, mem_flags))
			return -ENOMEM;
		return submit_async(ehci, urb, &qtd_list, mem_flags);

	case PIPE_INTERRUPT:
		if (!qh_urb_transaction (ehci, urb, &qtd_list, mem_flags))
			return -ENOMEM;
		return intr_submit(ehci, urb, &qtd_list, mem_flags);

	case PIPE_ISOCHRONOUS:
		if (urb->dev->speed == USB_SPEED_HIGH)
			return itd_submit (ehci, urb, mem_flags);
		else
			return sitd_submit (ehci, urb, mem_flags);
	}
}

/* remove from hardware lists
 * completions normally happen asynchronously
 */

static int ehci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
{
	struct ehci_hcd		*ehci = hcd_to_ehci (hcd);
	struct ehci_qh		*qh;
	unsigned long		flags;
	int			rc;

	spin_lock_irqsave (&ehci->lock, flags);
	rc = usb_hcd_check_unlink_urb(hcd, urb, status);
	if (rc)
		goto done;

	if (usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS) {
		/*
		 * We don't expedite dequeue for isochronous URBs.
		 * Just wait until they complete normally or their
		 * time slot expires.
		 */
	} else {
		qh = (struct ehci_qh *) urb->hcpriv;
		qh->exception = 1;
		switch (qh->qh_state) {
		case QH_STATE_LINKED:
			if (usb_pipetype(urb->pipe) == PIPE_INTERRUPT)
				start_unlink_intr(ehci, qh);
			else
				start_unlink_async(ehci, qh);
			break;
		case QH_STATE_COMPLETING:
			qh->dequeue_during_giveback = 1;
			break;
		case QH_STATE_UNLINK:
		case QH_STATE_UNLINK_WAIT:
			/* already started */
			break;
		case QH_STATE_IDLE:
			/* QH might be waiting for a Clear-TT-Buffer */
			qh_completions(ehci, qh);
			break;
		}
	}
done:
	spin_unlock_irqrestore (&ehci->lock, flags);
	return rc;
}

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

// bulk qh holds the data toggle

static void
ehci_endpoint_disable (struct usb_hcd *hcd, struct usb_host_endpoint *ep)
{
	struct ehci_hcd		*ehci = hcd_to_ehci (hcd);
	unsigned long		flags;
	struct ehci_qh		*qh;

	/* ASSERT:  any requests/urbs are being unlinked */
	/* ASSERT:  nobody can be submitting urbs for this any more */

rescan:
	spin_lock_irqsave (&ehci->lock, flags);
	qh = ep->hcpriv;
	if (!qh)
		goto done;

	/* endpoints can be iso streams.  for now, we don't
	 * accelerate iso completions ... so spin a while.
	 */
	if (qh->hw == NULL) {
		struct ehci_iso_stream	*stream = ep->hcpriv;

		if (!list_empty(&stream->td_list))
			goto idle_timeout;

		/* BUG_ON(!list_empty(&stream->free_list)); */
		reserve_release_iso_bandwidth(ehci, stream, -1);
		kfree(stream);
		goto done;
	}

	qh->exception = 1;
	switch (qh->qh_state) {
	case QH_STATE_LINKED:
		WARN_ON(!list_empty(&qh->qtd_list));
		if (usb_endpoint_type(&ep->desc) != USB_ENDPOINT_XFER_INT)
			start_unlink_async(ehci, qh);
		else
			start_unlink_intr(ehci, qh);
		/* FALL THROUGH */
	case QH_STATE_COMPLETING:	/* already in unlinking */
	case QH_STATE_UNLINK:		/* wait for hw to finish? */
	case QH_STATE_UNLINK_WAIT:
idle_timeout:
		spin_unlock_irqrestore (&ehci->lock, flags);
		schedule_timeout_uninterruptible(1);
		goto rescan;
	case QH_STATE_IDLE:		/* fully unlinked */
		if (qh->clearing_tt)
			goto idle_timeout;
		if (list_empty (&qh->qtd_list)) {
			if (qh->ps.bw_uperiod)
				reserve_release_intr_bandwidth(ehci, qh, -1);
			qh_destroy(ehci, qh);
			break;
		}
		/* else FALL THROUGH */
	default:
		/* caller was supposed to have unlinked any requests;
		 * that's not our job.  just leak this memory.
		 */
		ehci_err (ehci, "qh %p (#%02x) state %d%s\n",
			qh, ep->desc.bEndpointAddress, qh->qh_state,
			list_empty (&qh->qtd_list) ? "" : "(has tds)");
		break;
	}
 done:
	ep->hcpriv = NULL;
	spin_unlock_irqrestore (&ehci->lock, flags);
}

static void
ehci_endpoint_reset(struct usb_hcd *hcd, struct usb_host_endpoint *ep)
{
	struct ehci_hcd		*ehci = hcd_to_ehci(hcd);
	struct ehci_qh		*qh;
	int			eptype = usb_endpoint_type(&ep->desc);
	int			epnum = usb_endpoint_num(&ep->desc);
	int			is_out = usb_endpoint_dir_out(&ep->desc);
	unsigned long		flags;

	if (eptype != USB_ENDPOINT_XFER_BULK && eptype != USB_ENDPOINT_XFER_INT)
		return;

	spin_lock_irqsave(&ehci->lock, flags);
	qh = ep->hcpriv;

	/* For Bulk and Interrupt endpoints we maintain the toggle state
	 * in the hardware; the toggle bits in udev aren't used at all.
	 * When an endpoint is reset by usb_clear_halt() we must reset
	 * the toggle bit in the QH.
	 */
	if (qh) {
		if (!list_empty(&qh->qtd_list)) {
			WARN_ONCE(1, "clear_halt for a busy endpoint\n");
		} else {
			/* The toggle value in the QH can't be updated
			 * while the QH is active.  Unlink it now;
			 * re-linking will call qh_refresh().
			 */
			usb_settoggle(qh->ps.udev, epnum, is_out, 0);
			qh->exception = 1;
			if (eptype == USB_ENDPOINT_XFER_BULK)
				start_unlink_async(ehci, qh);
			else
				start_unlink_intr(ehci, qh);
		}
	}
	spin_unlock_irqrestore(&ehci->lock, flags);
}

static int ehci_get_frame (struct usb_hcd *hcd)
{
	struct ehci_hcd		*ehci = hcd_to_ehci (hcd);
	return (ehci_read_frame_index(ehci) >> 3) % ehci->periodic_size;
}

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

/* Device addition and removal */

static void ehci_remove_device(struct usb_hcd *hcd, struct usb_device *udev)
{
	struct ehci_hcd		*ehci = hcd_to_ehci(hcd);

	spin_lock_irq(&ehci->lock);
	drop_tt(udev);
	spin_unlock_irq(&ehci->lock);
}

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

#ifdef	CONFIG_PM

/* suspend/resume, section 4.3 */

/* These routines handle the generic parts of controller suspend/resume */

int ehci_suspend(struct usb_hcd *hcd, bool do_wakeup)
{
	struct ehci_hcd		*ehci = hcd_to_ehci(hcd);

	if (time_before(jiffies, ehci->next_statechange))
		msleep(10);

	/*
	 * Root hub was already suspended.  Disable IRQ emission and
	 * mark HW unaccessible.  The PM and USB cores make sure that
	 * the root hub is either suspended or stopped.
	 */
	ehci_prepare_ports_for_controller_suspend(ehci, do_wakeup);

	spin_lock_irq(&ehci->lock);
	ehci_writel(ehci, 0, &ehci->regs->intr_enable);
	(void) ehci_readl(ehci, &ehci->regs->intr_enable);

	clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
	spin_unlock_irq(&ehci->lock);

	synchronize_irq(hcd->irq);

	/* Check for race with a wakeup request */
	if (do_wakeup && HCD_WAKEUP_PENDING(hcd)) {
		ehci_resume(hcd, false);
		return -EBUSY;
	}

	return 0;
}
EXPORT_SYMBOL_GPL(ehci_suspend);

/* Returns 0 if power was preserved, 1 if power was lost */
int ehci_resume(struct usb_hcd *hcd, bool force_reset)
{
	struct ehci_hcd		*ehci = hcd_to_ehci(hcd);

	if (time_before(jiffies, ehci->next_statechange))
		msleep(100);

	/* Mark hardware accessible again as we are back to full power by now */
	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);

	if (ehci->shutdown)
		return 0;		/* Controller is dead */

	/*
	 * If CF is still set and reset isn't forced
	 * then we maintained suspend power.
	 * Just undo the effect of ehci_suspend().
	 */
	if (ehci_readl(ehci, &ehci->regs->configured_flag) == FLAG_CF &&
			!force_reset) {
		int	mask = INTR_MASK;

		ehci_prepare_ports_for_controller_resume(ehci);

		spin_lock_irq(&ehci->lock);
		if (ehci->shutdown)
			goto skip;

		if (!hcd->self.root_hub->do_remote_wakeup)
			mask &= ~STS_PCD;
		ehci_writel(ehci, mask, &ehci->regs->intr_enable);
		ehci_readl(ehci, &ehci->regs->intr_enable);
 skip:
		spin_unlock_irq(&ehci->lock);
		return 0;
	}

	/*
	 * Else reset, to cope with power loss or resume from hibernation
	 * having let the firmware kick in during reboot.
	 */
	usb_root_hub_lost_power(hcd->self.root_hub);
	(void) ehci_halt(ehci);
	(void) ehci_reset(ehci);

	spin_lock_irq(&ehci->lock);
	if (ehci->shutdown)
		goto skip;

	ehci_writel(ehci, ehci->command, &ehci->regs->command);
	ehci_writel(ehci, FLAG_CF, &ehci->regs->configured_flag);
	ehci_readl(ehci, &ehci->regs->command);	/* unblock posted writes */

	ehci->rh_state = EHCI_RH_SUSPENDED;
	spin_unlock_irq(&ehci->lock);

	return 1;
}
EXPORT_SYMBOL_GPL(ehci_resume);

#endif

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

/*
 * Generic structure: This gets copied for platform drivers so that
 * individual entries can be overridden as needed.
 */

static const struct hc_driver ehci_hc_driver = {
	.description =		hcd_name,
	.product_desc =		"EHCI Host Controller",
	.hcd_priv_size =	sizeof(struct ehci_hcd),

	/*
	 * generic hardware linkage
	 */
	.irq =			ehci_irq,
	.flags =		HCD_MEMORY | HCD_USB2 | HCD_BH,

	/*
	 * basic lifecycle operations
	 */
	.reset =		ehci_setup,
	.start =		ehci_run,
	.stop =			ehci_stop,
	.shutdown =		ehci_shutdown,

	/*
	 * managing i/o requests and associated device resources
	 */
	.urb_enqueue =		ehci_urb_enqueue,
	.urb_dequeue =		ehci_urb_dequeue,
	.endpoint_disable =	ehci_endpoint_disable,
	.endpoint_reset =	ehci_endpoint_reset,
	.clear_tt_buffer_complete =	ehci_clear_tt_buffer_complete,

	/*
	 * scheduling support
	 */
	.get_frame_number =	ehci_get_frame,

	/*
	 * root hub support
	 */
	.hub_status_data =	ehci_hub_status_data,
	.hub_control =		ehci_hub_control,
	.bus_suspend =		ehci_bus_suspend,
	.bus_resume =		ehci_bus_resume,
	.relinquish_port =	ehci_relinquish_port,
	.port_handed_over =	ehci_port_handed_over,

	/*
	 * device support
	 */
	.free_dev =		ehci_remove_device,
};

void ehci_init_driver(struct hc_driver *drv,
		const struct ehci_driver_overrides *over)
{
	/* Copy the generic table to drv and then apply the overrides */
	*drv = ehci_hc_driver;

	if (over) {
		drv->hcd_priv_size += over->extra_priv_size;
		if (over->reset)
			drv->reset = over->reset;
		if (over->port_power)
			drv->port_power = over->port_power;
	}
}
EXPORT_SYMBOL_GPL(ehci_init_driver);

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

MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_AUTHOR (DRIVER_AUTHOR);
MODULE_LICENSE ("GPL");

#ifdef CONFIG_USB_EHCI_SH
#include "ehci-sh.c"
#define PLATFORM_DRIVER		ehci_hcd_sh_driver
#endif

#ifdef CONFIG_PPC_PS3
#include "ehci-ps3.c"
#define	PS3_SYSTEM_BUS_DRIVER	ps3_ehci_driver
#endif

#ifdef CONFIG_USB_EHCI_HCD_PPC_OF
#include "ehci-ppc-of.c"
#define OF_PLATFORM_DRIVER	ehci_hcd_ppc_of_driver
#endif

#ifdef CONFIG_XPS_USB_HCD_XILINX
#include "ehci-xilinx-of.c"
#define XILINX_OF_PLATFORM_DRIVER	ehci_hcd_xilinx_of_driver
#endif

#ifdef CONFIG_TILE_USB
#include "ehci-tilegx.c"
#define	PLATFORM_DRIVER		ehci_hcd_tilegx_driver
#endif

#ifdef CONFIG_USB_EHCI_HCD_PMC_MSP
#include "ehci-pmcmsp.c"
#define	PLATFORM_DRIVER		ehci_hcd_msp_driver
#endif

#ifdef CONFIG_SPARC_LEON
#include "ehci-grlib.c"
#define PLATFORM_DRIVER		ehci_grlib_driver
#endif

#ifdef CONFIG_USB_EHCI_MV
#include "ehci-mv.c"
#define        PLATFORM_DRIVER         ehci_mv_driver
#endif

#ifdef CONFIG_MIPS_SEAD3
#include "ehci-sead3.c"
#define	PLATFORM_DRIVER		ehci_hcd_sead3_driver
#endif

static int __init ehci_hcd_init(void)
{
	int retval = 0;

	if (usb_disabled())
		return -ENODEV;

	printk(KERN_INFO "%s: " DRIVER_DESC "\n", hcd_name);
	set_bit(USB_EHCI_LOADED, &usb_hcds_loaded);
	if (test_bit(USB_UHCI_LOADED, &usb_hcds_loaded) ||
			test_bit(USB_OHCI_LOADED, &usb_hcds_loaded))
		printk(KERN_WARNING "Warning! ehci_hcd should always be loaded"
				" before uhci_hcd and ohci_hcd, not after\n");

	pr_debug("%s: block sizes: qh %Zd qtd %Zd itd %Zd sitd %Zd\n",
		 hcd_name,
		 sizeof(struct ehci_qh), sizeof(struct ehci_qtd),
		 sizeof(struct ehci_itd), sizeof(struct ehci_sitd));

#ifdef CONFIG_DYNAMIC_DEBUG
	ehci_debug_root = debugfs_create_dir("ehci", usb_debug_root);
	if (!ehci_debug_root) {
		retval = -ENOENT;
		goto err_debug;
	}
#endif

#ifdef PLATFORM_DRIVER
	retval = platform_driver_register(&PLATFORM_DRIVER);
	if (retval < 0)
		goto clean0;
#endif

#ifdef PS3_SYSTEM_BUS_DRIVER
	retval = ps3_ehci_driver_register(&PS3_SYSTEM_BUS_DRIVER);
	if (retval < 0)
		goto clean2;
#endif

#ifdef OF_PLATFORM_DRIVER
	retval = platform_driver_register(&OF_PLATFORM_DRIVER);
	if (retval < 0)
		goto clean3;
#endif

#ifdef XILINX_OF_PLATFORM_DRIVER
	retval = platform_driver_register(&XILINX_OF_PLATFORM_DRIVER);
	if (retval < 0)
		goto clean4;
#endif
	return retval;

#ifdef XILINX_OF_PLATFORM_DRIVER
	/* platform_driver_unregister(&XILINX_OF_PLATFORM_DRIVER); */
clean4:
#endif
#ifdef OF_PLATFORM_DRIVER
	platform_driver_unregister(&OF_PLATFORM_DRIVER);
clean3:
#endif
#ifdef PS3_SYSTEM_BUS_DRIVER
	ps3_ehci_driver_unregister(&PS3_SYSTEM_BUS_DRIVER);
clean2:
#endif
#ifdef PLATFORM_DRIVER
	platform_driver_unregister(&PLATFORM_DRIVER);
clean0:
#endif
#ifdef CONFIG_DYNAMIC_DEBUG
	debugfs_remove(ehci_debug_root);
	ehci_debug_root = NULL;
err_debug:
#endif
	clear_bit(USB_EHCI_LOADED, &usb_hcds_loaded);
	return retval;
}
module_init(ehci_hcd_init);

static void __exit ehci_hcd_cleanup(void)
{
#ifdef XILINX_OF_PLATFORM_DRIVER
	platform_driver_unregister(&XILINX_OF_PLATFORM_DRIVER);
#endif
#ifdef OF_PLATFORM_DRIVER
	platform_driver_unregister(&OF_PLATFORM_DRIVER);
#endif
#ifdef PLATFORM_DRIVER
	platform_driver_unregister(&PLATFORM_DRIVER);
#endif
#ifdef PS3_SYSTEM_BUS_DRIVER
	ps3_ehci_driver_unregister(&PS3_SYSTEM_BUS_DRIVER);
#endif
#ifdef CONFIG_DYNAMIC_DEBUG
	debugfs_remove(ehci_debug_root);
#endif
	clear_bit(USB_EHCI_LOADED, &usb_hcds_loaded);
}
module_exit(ehci_hcd_cleanup);