summaryrefslogtreecommitdiffstats
path: root/drivers/nfc/pn533.c
blob: 1a1500bc845233dc1537ea2b05c35379c33907e5 (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
/*
 * Copyright (C) 2011 Instituto Nokia de Tecnologia
 *
 * Authors:
 *    Lauro Ramos Venancio <lauro.venancio@openbossa.org>
 *    Aloisio Almeida Jr <aloisio.almeida@openbossa.org>
 *
 * 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.,
 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/usb.h>
#include <linux/nfc.h>
#include <linux/netdevice.h>
#include <net/nfc/nfc.h>

#define VERSION "0.1"

#define PN533_VENDOR_ID 0x4CC
#define PN533_PRODUCT_ID 0x2533

#define SCM_VENDOR_ID 0x4E6
#define SCL3711_PRODUCT_ID 0x5591

static const struct usb_device_id pn533_table[] = {
	{ USB_DEVICE(PN533_VENDOR_ID, PN533_PRODUCT_ID) },
	{ USB_DEVICE(SCM_VENDOR_ID, SCL3711_PRODUCT_ID) },
	{ }
};
MODULE_DEVICE_TABLE(usb, pn533_table);

/* frame definitions */
#define PN533_FRAME_TAIL_SIZE 2
#define PN533_FRAME_SIZE(f) (sizeof(struct pn533_frame) + f->datalen + \
				PN533_FRAME_TAIL_SIZE)
#define PN533_FRAME_ACK_SIZE (sizeof(struct pn533_frame) + 1)
#define PN533_FRAME_CHECKSUM(f) (f->data[f->datalen])
#define PN533_FRAME_POSTAMBLE(f) (f->data[f->datalen + 1])

/* start of frame */
#define PN533_SOF 0x00FF

/* frame identifier: in/out/error */
#define PN533_FRAME_IDENTIFIER(f) (f->data[0])
#define PN533_DIR_OUT 0xD4
#define PN533_DIR_IN 0xD5

/* PN533 Commands */
#define PN533_FRAME_CMD(f) (f->data[1])
#define PN533_FRAME_CMD_PARAMS_PTR(f) (&f->data[2])
#define PN533_FRAME_CMD_PARAMS_LEN(f) (f->datalen - 2)

#define PN533_CMD_GET_FIRMWARE_VERSION 0x02
#define PN533_CMD_RF_CONFIGURATION 0x32
#define PN533_CMD_IN_DATA_EXCHANGE 0x40
#define PN533_CMD_IN_LIST_PASSIVE_TARGET 0x4A
#define PN533_CMD_IN_ATR 0x50
#define PN533_CMD_IN_RELEASE 0x52
#define PN533_CMD_IN_JUMP_FOR_DEP 0x56

#define PN533_CMD_RESPONSE(cmd) (cmd + 1)

/* PN533 Return codes */
#define PN533_CMD_RET_MASK 0x3F
#define PN533_CMD_MI_MASK 0x40
#define PN533_CMD_RET_SUCCESS 0x00

struct pn533;

typedef int (*pn533_cmd_complete_t) (struct pn533 *dev, void *arg,
					u8 *params, int params_len);

/* structs for pn533 commands */

/* PN533_CMD_GET_FIRMWARE_VERSION */
struct pn533_fw_version {
	u8 ic;
	u8 ver;
	u8 rev;
	u8 support;
};

/* PN533_CMD_RF_CONFIGURATION */
#define PN533_CFGITEM_MAX_RETRIES 0x05

#define PN533_CONFIG_MAX_RETRIES_NO_RETRY 0x00
#define PN533_CONFIG_MAX_RETRIES_ENDLESS 0xFF

struct pn533_config_max_retries {
	u8 mx_rty_atr;
	u8 mx_rty_psl;
	u8 mx_rty_passive_act;
} __packed;

/* PN533_CMD_IN_LIST_PASSIVE_TARGET */

/* felica commands opcode */
#define PN533_FELICA_OPC_SENSF_REQ 0
#define PN533_FELICA_OPC_SENSF_RES 1
/* felica SENSF_REQ parameters */
#define PN533_FELICA_SENSF_SC_ALL 0xFFFF
#define PN533_FELICA_SENSF_RC_NO_SYSTEM_CODE 0
#define PN533_FELICA_SENSF_RC_SYSTEM_CODE 1
#define PN533_FELICA_SENSF_RC_ADVANCED_PROTOCOL 2

/* type B initiator_data values */
#define PN533_TYPE_B_AFI_ALL_FAMILIES 0
#define PN533_TYPE_B_POLL_METHOD_TIMESLOT 0
#define PN533_TYPE_B_POLL_METHOD_PROBABILISTIC 1

union pn533_cmd_poll_initdata {
	struct {
		u8 afi;
		u8 polling_method;
	} __packed type_b;
	struct {
		u8 opcode;
		__be16 sc;
		u8 rc;
		u8 tsn;
	} __packed felica;
};

/* Poll modulations */
enum {
	PN533_POLL_MOD_106KBPS_A,
	PN533_POLL_MOD_212KBPS_FELICA,
	PN533_POLL_MOD_424KBPS_FELICA,
	PN533_POLL_MOD_106KBPS_JEWEL,
	PN533_POLL_MOD_847KBPS_B,

	__PN533_POLL_MOD_AFTER_LAST,
};
#define PN533_POLL_MOD_MAX (__PN533_POLL_MOD_AFTER_LAST - 1)

struct pn533_poll_modulations {
	struct {
		u8 maxtg;
		u8 brty;
		union pn533_cmd_poll_initdata initiator_data;
	} __packed data;
	u8 len;
};

const struct pn533_poll_modulations poll_mod[] = {
	[PN533_POLL_MOD_106KBPS_A] = {
		.data = {
			.maxtg = 1,
			.brty = 0,
		},
		.len = 2,
	},
	[PN533_POLL_MOD_212KBPS_FELICA] = {
		.data = {
			.maxtg = 1,
			.brty = 1,
			.initiator_data.felica = {
				.opcode = PN533_FELICA_OPC_SENSF_REQ,
				.sc = PN533_FELICA_SENSF_SC_ALL,
				.rc = PN533_FELICA_SENSF_RC_NO_SYSTEM_CODE,
				.tsn = 0,
			},
		},
		.len = 7,
	},
	[PN533_POLL_MOD_424KBPS_FELICA] = {
		.data = {
			.maxtg = 1,
			.brty = 2,
			.initiator_data.felica = {
				.opcode = PN533_FELICA_OPC_SENSF_REQ,
				.sc = PN533_FELICA_SENSF_SC_ALL,
				.rc = PN533_FELICA_SENSF_RC_NO_SYSTEM_CODE,
				.tsn = 0,
			},
		 },
		.len = 7,
	},
	[PN533_POLL_MOD_106KBPS_JEWEL] = {
		.data = {
			.maxtg = 1,
			.brty = 4,
		},
		.len = 2,
	},
	[PN533_POLL_MOD_847KBPS_B] = {
		.data = {
			.maxtg = 1,
			.brty = 8,
			.initiator_data.type_b = {
				.afi = PN533_TYPE_B_AFI_ALL_FAMILIES,
				.polling_method =
					PN533_TYPE_B_POLL_METHOD_TIMESLOT,
			},
		},
		.len = 3,
	},
};

/* PN533_CMD_IN_ATR */

struct pn533_cmd_activate_param {
	u8 tg;
	u8 next;
} __packed;

struct pn533_cmd_activate_response {
	u8 status;
	u8 nfcid3t[10];
	u8 didt;
	u8 bst;
	u8 brt;
	u8 to;
	u8 ppt;
	/* optional */
	u8 gt[];
} __packed;

/* PN533_CMD_IN_JUMP_FOR_DEP */
struct pn533_cmd_jump_dep {
	u8 active;
	u8 baud;
	u8 next;
	u8 gt[];
} __packed;

struct pn533_cmd_jump_dep_response {
	u8 status;
	u8 tg;
	u8 nfcid3t[10];
	u8 didt;
	u8 bst;
	u8 brt;
	u8 to;
	u8 ppt;
	/* optional */
	u8 gt[];
} __packed;

struct pn533 {
	struct usb_device *udev;
	struct usb_interface *interface;
	struct nfc_dev *nfc_dev;

	struct urb *out_urb;
	int out_maxlen;
	struct pn533_frame *out_frame;

	struct urb *in_urb;
	int in_maxlen;
	struct pn533_frame *in_frame;

	struct tasklet_struct tasklet;
	struct pn533_frame *tklt_in_frame;
	int tklt_in_error;

	pn533_cmd_complete_t cmd_complete;
	void *cmd_complete_arg;
	struct semaphore cmd_lock;
	u8 cmd;

	struct pn533_poll_modulations *poll_mod_active[PN533_POLL_MOD_MAX + 1];
	u8 poll_mod_count;
	u8 poll_mod_curr;
	u32 poll_protocols;

	u8 tgt_available_prots;
	u8 tgt_active_prot;
};

struct pn533_frame {
	u8 preamble;
	__be16 start_frame;
	u8 datalen;
	u8 datalen_checksum;
	u8 data[];
} __packed;

/* The rule: value + checksum = 0 */
static inline u8 pn533_checksum(u8 value)
{
	return ~value + 1;
}

/* The rule: sum(data elements) + checksum = 0 */
static u8 pn533_data_checksum(u8 *data, int datalen)
{
	u8 sum = 0;
	int i;

	for (i = 0; i < datalen; i++)
		sum += data[i];

	return pn533_checksum(sum);
}

/**
 * pn533_tx_frame_ack - create a ack frame
 * @frame:	The frame to be set as ack
 *
 * Ack is different type of standard frame. As a standard frame, it has
 * preamble and start_frame. However the checksum of this frame must fail,
 * i.e. datalen + datalen_checksum must NOT be zero. When the checksum test
 * fails and datalen = 0 and datalen_checksum = 0xFF, the frame is a ack.
 * After datalen_checksum field, the postamble is placed.
 */
static void pn533_tx_frame_ack(struct pn533_frame *frame)
{
	frame->preamble = 0;
	frame->start_frame = cpu_to_be16(PN533_SOF);
	frame->datalen = 0;
	frame->datalen_checksum = 0xFF;
	/* data[0] is used as postamble */
	frame->data[0] = 0;
}

static void pn533_tx_frame_init(struct pn533_frame *frame, u8 cmd)
{
	frame->preamble = 0;
	frame->start_frame = cpu_to_be16(PN533_SOF);
	PN533_FRAME_IDENTIFIER(frame) = PN533_DIR_OUT;
	PN533_FRAME_CMD(frame) = cmd;
	frame->datalen = 2;
}

static void pn533_tx_frame_finish(struct pn533_frame *frame)
{
	frame->datalen_checksum = pn533_checksum(frame->datalen);

	PN533_FRAME_CHECKSUM(frame) =
		pn533_data_checksum(frame->data, frame->datalen);

	PN533_FRAME_POSTAMBLE(frame) = 0;
}

static bool pn533_rx_frame_is_valid(struct pn533_frame *frame)
{
	u8 checksum;

	if (frame->start_frame != cpu_to_be16(PN533_SOF))
		return false;

	checksum = pn533_checksum(frame->datalen);
	if (checksum != frame->datalen_checksum)
		return false;

	checksum = pn533_data_checksum(frame->data, frame->datalen);
	if (checksum != PN533_FRAME_CHECKSUM(frame))
		return false;

	return true;
}

static bool pn533_rx_frame_is_ack(struct pn533_frame *frame)
{
	if (frame->start_frame != cpu_to_be16(PN533_SOF))
		return false;

	if (frame->datalen != 0 || frame->datalen_checksum != 0xFF)
		return false;

	return true;
}

static bool pn533_rx_frame_is_cmd_response(struct pn533_frame *frame, u8 cmd)
{
	return (PN533_FRAME_CMD(frame) == PN533_CMD_RESPONSE(cmd));
}

static void pn533_tasklet_cmd_complete(unsigned long arg)
{
	struct pn533 *dev = (struct pn533 *) arg;
	struct pn533_frame *in_frame = dev->tklt_in_frame;
	int rc;

	if (dev->tklt_in_error)
		rc = dev->cmd_complete(dev, dev->cmd_complete_arg, NULL,
							dev->tklt_in_error);
	else
		rc = dev->cmd_complete(dev, dev->cmd_complete_arg,
					PN533_FRAME_CMD_PARAMS_PTR(in_frame),
					PN533_FRAME_CMD_PARAMS_LEN(in_frame));

	if (rc != -EINPROGRESS)
		up(&dev->cmd_lock);
}

static void pn533_recv_response(struct urb *urb)
{
	struct pn533 *dev = urb->context;
	struct pn533_frame *in_frame;

	dev->tklt_in_frame = NULL;

	switch (urb->status) {
	case 0:
		/* success */
		break;
	case -ECONNRESET:
	case -ENOENT:
	case -ESHUTDOWN:
		nfc_dev_dbg(&dev->interface->dev, "Urb shutting down with"
						" status: %d", urb->status);
		dev->tklt_in_error = urb->status;
		goto sched_tasklet;
	default:
		nfc_dev_err(&dev->interface->dev, "Nonzero urb status received:"
							" %d", urb->status);
		dev->tklt_in_error = urb->status;
		goto sched_tasklet;
	}

	in_frame = dev->in_urb->transfer_buffer;

	if (!pn533_rx_frame_is_valid(in_frame)) {
		nfc_dev_err(&dev->interface->dev, "Received an invalid frame");
		dev->tklt_in_error = -EIO;
		goto sched_tasklet;
	}

	if (!pn533_rx_frame_is_cmd_response(in_frame, dev->cmd)) {
		nfc_dev_err(&dev->interface->dev, "The received frame is not "
						"response to the last command");
		dev->tklt_in_error = -EIO;
		goto sched_tasklet;
	}

	nfc_dev_dbg(&dev->interface->dev, "Received a valid frame");
	dev->tklt_in_error = 0;
	dev->tklt_in_frame = in_frame;

sched_tasklet:
	tasklet_schedule(&dev->tasklet);
}

static int pn533_submit_urb_for_response(struct pn533 *dev, gfp_t flags)
{
	dev->in_urb->complete = pn533_recv_response;

	return usb_submit_urb(dev->in_urb, flags);
}

static void pn533_recv_ack(struct urb *urb)
{
	struct pn533 *dev = urb->context;
	struct pn533_frame *in_frame;
	int rc;

	switch (urb->status) {
	case 0:
		/* success */
		break;
	case -ECONNRESET:
	case -ENOENT:
	case -ESHUTDOWN:
		nfc_dev_dbg(&dev->interface->dev, "Urb shutting down with"
						" status: %d", urb->status);
		dev->tklt_in_error = urb->status;
		goto sched_tasklet;
	default:
		nfc_dev_err(&dev->interface->dev, "Nonzero urb status received:"
							" %d", urb->status);
		dev->tklt_in_error = urb->status;
		goto sched_tasklet;
	}

	in_frame = dev->in_urb->transfer_buffer;

	if (!pn533_rx_frame_is_ack(in_frame)) {
		nfc_dev_err(&dev->interface->dev, "Received an invalid ack");
		dev->tklt_in_error = -EIO;
		goto sched_tasklet;
	}

	nfc_dev_dbg(&dev->interface->dev, "Received a valid ack");

	rc = pn533_submit_urb_for_response(dev, GFP_ATOMIC);
	if (rc) {
		nfc_dev_err(&dev->interface->dev, "usb_submit_urb failed with"
							" result %d", rc);
		dev->tklt_in_error = rc;
		goto sched_tasklet;
	}

	return;

sched_tasklet:
	dev->tklt_in_frame = NULL;
	tasklet_schedule(&dev->tasklet);
}

static int pn533_submit_urb_for_ack(struct pn533 *dev, gfp_t flags)
{
	dev->in_urb->complete = pn533_recv_ack;

	return usb_submit_urb(dev->in_urb, flags);
}

static int pn533_send_ack(struct pn533 *dev, gfp_t flags)
{
	int rc;

	nfc_dev_dbg(&dev->interface->dev, "%s", __func__);

	pn533_tx_frame_ack(dev->out_frame);

	dev->out_urb->transfer_buffer = dev->out_frame;
	dev->out_urb->transfer_buffer_length = PN533_FRAME_ACK_SIZE;
	rc = usb_submit_urb(dev->out_urb, flags);

	return rc;
}

static int __pn533_send_cmd_frame_async(struct pn533 *dev,
					struct pn533_frame *out_frame,
					struct pn533_frame *in_frame,
					int in_frame_len,
					pn533_cmd_complete_t cmd_complete,
					void *arg, gfp_t flags)
{
	int rc;

	nfc_dev_dbg(&dev->interface->dev, "Sending command 0x%x",
						PN533_FRAME_CMD(out_frame));

	dev->cmd = PN533_FRAME_CMD(out_frame);
	dev->cmd_complete = cmd_complete;
	dev->cmd_complete_arg = arg;

	dev->out_urb->transfer_buffer = out_frame;
	dev->out_urb->transfer_buffer_length =
				PN533_FRAME_SIZE(out_frame);

	dev->in_urb->transfer_buffer = in_frame;
	dev->in_urb->transfer_buffer_length = in_frame_len;

	rc = usb_submit_urb(dev->out_urb, flags);
	if (rc)
		return rc;

	rc = pn533_submit_urb_for_ack(dev, flags);
	if (rc)
		goto error;

	return 0;

error:
	usb_unlink_urb(dev->out_urb);
	return rc;
}

static int pn533_send_cmd_frame_async(struct pn533 *dev,
					struct pn533_frame *out_frame,
					struct pn533_frame *in_frame,
					int in_frame_len,
					pn533_cmd_complete_t cmd_complete,
					void *arg, gfp_t flags)
{
	int rc;

	nfc_dev_dbg(&dev->interface->dev, "%s", __func__);

	if (down_trylock(&dev->cmd_lock))
		return -EBUSY;

	rc = __pn533_send_cmd_frame_async(dev, out_frame, in_frame,
					in_frame_len, cmd_complete, arg, flags);
	if (rc)
		goto error;

	return 0;
error:
	up(&dev->cmd_lock);
	return rc;
}

struct pn533_sync_cmd_response {
	int rc;
	struct completion done;
};

static int pn533_sync_cmd_complete(struct pn533 *dev, void *_arg,
					u8 *params, int params_len)
{
	struct pn533_sync_cmd_response *arg = _arg;

	nfc_dev_dbg(&dev->interface->dev, "%s", __func__);

	arg->rc = 0;

	if (params_len < 0) /* error */
		arg->rc = params_len;

	complete(&arg->done);

	return 0;
}

static int pn533_send_cmd_frame_sync(struct pn533 *dev,
						struct pn533_frame *out_frame,
						struct pn533_frame *in_frame,
						int in_frame_len)
{
	int rc;
	struct pn533_sync_cmd_response arg;

	nfc_dev_dbg(&dev->interface->dev, "%s", __func__);

	init_completion(&arg.done);

	rc = pn533_send_cmd_frame_async(dev, out_frame, in_frame, in_frame_len,
				pn533_sync_cmd_complete, &arg, GFP_KERNEL);
	if (rc)
		return rc;

	wait_for_completion(&arg.done);

	return arg.rc;
}

static void pn533_send_complete(struct urb *urb)
{
	struct pn533 *dev = urb->context;

	nfc_dev_dbg(&dev->interface->dev, "%s", __func__);

	switch (urb->status) {
	case 0:
		/* success */
		break;
	case -ECONNRESET:
	case -ENOENT:
	case -ESHUTDOWN:
		nfc_dev_dbg(&dev->interface->dev, "Urb shutting down with"
						" status: %d", urb->status);
		break;
	default:
		nfc_dev_dbg(&dev->interface->dev, "Nonzero urb status received:"
							" %d", urb->status);
	}
}

struct pn533_target_type_a {
	__be16 sens_res;
	u8 sel_res;
	u8 nfcid_len;
	u8 nfcid_data[];
} __packed;


#define PN533_TYPE_A_SENS_RES_NFCID1(x) ((u8)((be16_to_cpu(x) & 0x00C0) >> 6))
#define PN533_TYPE_A_SENS_RES_SSD(x) ((u8)((be16_to_cpu(x) & 0x001F) >> 0))
#define PN533_TYPE_A_SENS_RES_PLATCONF(x) ((u8)((be16_to_cpu(x) & 0x0F00) >> 8))

#define PN533_TYPE_A_SENS_RES_SSD_JEWEL 0x00
#define PN533_TYPE_A_SENS_RES_PLATCONF_JEWEL 0x0C

#define PN533_TYPE_A_SEL_PROT(x) (((x) & 0x60) >> 5)
#define PN533_TYPE_A_SEL_CASCADE(x) (((x) & 0x04) >> 2)

#define PN533_TYPE_A_SEL_PROT_MIFARE 0
#define PN533_TYPE_A_SEL_PROT_ISO14443 1
#define PN533_TYPE_A_SEL_PROT_DEP 2
#define PN533_TYPE_A_SEL_PROT_ISO14443_DEP 3

static bool pn533_target_type_a_is_valid(struct pn533_target_type_a *type_a,
							int target_data_len)
{
	u8 ssd;
	u8 platconf;

	if (target_data_len < sizeof(struct pn533_target_type_a))
		return false;

	/* The lenght check of nfcid[] and ats[] are not being performed because
	   the values are not being used */

	/* Requirement 4.6.3.3 from NFC Forum Digital Spec */
	ssd = PN533_TYPE_A_SENS_RES_SSD(type_a->sens_res);
	platconf = PN533_TYPE_A_SENS_RES_PLATCONF(type_a->sens_res);

	if ((ssd == PN533_TYPE_A_SENS_RES_SSD_JEWEL &&
			platconf != PN533_TYPE_A_SENS_RES_PLATCONF_JEWEL) ||
			(ssd != PN533_TYPE_A_SENS_RES_SSD_JEWEL &&
			platconf == PN533_TYPE_A_SENS_RES_PLATCONF_JEWEL))
		return false;

	/* Requirements 4.8.2.1, 4.8.2.3, 4.8.2.5 and 4.8.2.7 from NFC Forum */
	if (PN533_TYPE_A_SEL_CASCADE(type_a->sel_res) != 0)
		return false;

	return true;
}

static int pn533_target_found_type_a(struct nfc_target *nfc_tgt, u8 *tgt_data,
							int tgt_data_len)
{
	struct pn533_target_type_a *tgt_type_a;

	tgt_type_a = (struct pn533_target_type_a *) tgt_data;

	if (!pn533_target_type_a_is_valid(tgt_type_a, tgt_data_len))
		return -EPROTO;

	switch (PN533_TYPE_A_SEL_PROT(tgt_type_a->sel_res)) {
	case PN533_TYPE_A_SEL_PROT_MIFARE:
		nfc_tgt->supported_protocols = NFC_PROTO_MIFARE_MASK;
		break;
	case PN533_TYPE_A_SEL_PROT_ISO14443:
		nfc_tgt->supported_protocols = NFC_PROTO_ISO14443_MASK;
		break;
	case PN533_TYPE_A_SEL_PROT_DEP:
		nfc_tgt->supported_protocols = NFC_PROTO_NFC_DEP_MASK;
		break;
	case PN533_TYPE_A_SEL_PROT_ISO14443_DEP:
		nfc_tgt->supported_protocols = NFC_PROTO_ISO14443_MASK |
							NFC_PROTO_NFC_DEP_MASK;
		break;
	}

	nfc_tgt->sens_res = be16_to_cpu(tgt_type_a->sens_res);
	nfc_tgt->sel_res = tgt_type_a->sel_res;

	return 0;
}

struct pn533_target_felica {
	u8 pol_res;
	u8 opcode;
	u8 nfcid2[8];
	u8 pad[8];
	/* optional */
	u8 syst_code[];
} __packed;

#define PN533_FELICA_SENSF_NFCID2_DEP_B1 0x01
#define PN533_FELICA_SENSF_NFCID2_DEP_B2 0xFE

static bool pn533_target_felica_is_valid(struct pn533_target_felica *felica,
							int target_data_len)
{
	if (target_data_len < sizeof(struct pn533_target_felica))
		return false;

	if (felica->opcode != PN533_FELICA_OPC_SENSF_RES)
		return false;

	return true;
}

static int pn533_target_found_felica(struct nfc_target *nfc_tgt, u8 *tgt_data,
							int tgt_data_len)
{
	struct pn533_target_felica *tgt_felica;

	tgt_felica = (struct pn533_target_felica *) tgt_data;

	if (!pn533_target_felica_is_valid(tgt_felica, tgt_data_len))
		return -EPROTO;

	if (tgt_felica->nfcid2[0] == PN533_FELICA_SENSF_NFCID2_DEP_B1 &&
					tgt_felica->nfcid2[1] ==
					PN533_FELICA_SENSF_NFCID2_DEP_B2)
		nfc_tgt->supported_protocols = NFC_PROTO_NFC_DEP_MASK;
	else
		nfc_tgt->supported_protocols = NFC_PROTO_FELICA_MASK;

	return 0;
}

struct pn533_target_jewel {
	__be16 sens_res;
	u8 jewelid[4];
} __packed;

static bool pn533_target_jewel_is_valid(struct pn533_target_jewel *jewel,
							int target_data_len)
{
	u8 ssd;
	u8 platconf;

	if (target_data_len < sizeof(struct pn533_target_jewel))
		return false;

	/* Requirement 4.6.3.3 from NFC Forum Digital Spec */
	ssd = PN533_TYPE_A_SENS_RES_SSD(jewel->sens_res);
	platconf = PN533_TYPE_A_SENS_RES_PLATCONF(jewel->sens_res);

	if ((ssd == PN533_TYPE_A_SENS_RES_SSD_JEWEL &&
			platconf != PN533_TYPE_A_SENS_RES_PLATCONF_JEWEL) ||
			(ssd != PN533_TYPE_A_SENS_RES_SSD_JEWEL &&
			platconf == PN533_TYPE_A_SENS_RES_PLATCONF_JEWEL))
		return false;

	return true;
}

static int pn533_target_found_jewel(struct nfc_target *nfc_tgt, u8 *tgt_data,
							int tgt_data_len)
{
	struct pn533_target_jewel *tgt_jewel;

	tgt_jewel = (struct pn533_target_jewel *) tgt_data;

	if (!pn533_target_jewel_is_valid(tgt_jewel, tgt_data_len))
		return -EPROTO;

	nfc_tgt->supported_protocols = NFC_PROTO_JEWEL_MASK;
	nfc_tgt->sens_res = be16_to_cpu(tgt_jewel->sens_res);

	return 0;
}

struct pn533_type_b_prot_info {
	u8 bitrate;
	u8 fsci_type;
	u8 fwi_adc_fo;
} __packed;

#define PN533_TYPE_B_PROT_FCSI(x) (((x) & 0xF0) >> 4)
#define PN533_TYPE_B_PROT_TYPE(x) (((x) & 0x0F) >> 0)
#define PN533_TYPE_B_PROT_TYPE_RFU_MASK 0x8

struct pn533_type_b_sens_res {
	u8 opcode;
	u8 nfcid[4];
	u8 appdata[4];
	struct pn533_type_b_prot_info prot_info;
} __packed;

#define PN533_TYPE_B_OPC_SENSB_RES 0x50

struct pn533_target_type_b {
	struct pn533_type_b_sens_res sensb_res;
	u8 attrib_res_len;
	u8 attrib_res[];
} __packed;

static bool pn533_target_type_b_is_valid(struct pn533_target_type_b *type_b,
							int target_data_len)
{
	if (target_data_len < sizeof(struct pn533_target_type_b))
		return false;

	if (type_b->sensb_res.opcode != PN533_TYPE_B_OPC_SENSB_RES)
		return false;

	if (PN533_TYPE_B_PROT_TYPE(type_b->sensb_res.prot_info.fsci_type) &
						PN533_TYPE_B_PROT_TYPE_RFU_MASK)
		return false;

	return true;
}

static int pn533_target_found_type_b(struct nfc_target *nfc_tgt, u8 *tgt_data,
							int tgt_data_len)
{
	struct pn533_target_type_b *tgt_type_b;

	tgt_type_b = (struct pn533_target_type_b *) tgt_data;

	if (!pn533_target_type_b_is_valid(tgt_type_b, tgt_data_len))
		return -EPROTO;

	nfc_tgt->supported_protocols = NFC_PROTO_ISO14443_MASK;

	return 0;
}

struct pn533_poll_response {
	u8 nbtg;
	u8 tg;
	u8 target_data[];
} __packed;

static int pn533_target_found(struct pn533 *dev,
			struct pn533_poll_response *resp, int resp_len)
{
	int target_data_len;
	struct nfc_target nfc_tgt;
	int rc;

	nfc_dev_dbg(&dev->interface->dev, "%s - modulation=%d", __func__,
							dev->poll_mod_curr);

	if (resp->tg != 1)
		return -EPROTO;

	target_data_len = resp_len - sizeof(struct pn533_poll_response);

	switch (dev->poll_mod_curr) {
	case PN533_POLL_MOD_106KBPS_A:
		rc = pn533_target_found_type_a(&nfc_tgt, resp->target_data,
							target_data_len);
		break;
	case PN533_POLL_MOD_212KBPS_FELICA:
	case PN533_POLL_MOD_424KBPS_FELICA:
		rc = pn533_target_found_felica(&nfc_tgt, resp->target_data,
							target_data_len);
		break;
	case PN533_POLL_MOD_106KBPS_JEWEL:
		rc = pn533_target_found_jewel(&nfc_tgt, resp->target_data,
							target_data_len);
		break;
	case PN533_POLL_MOD_847KBPS_B:
		rc = pn533_target_found_type_b(&nfc_tgt, resp->target_data,
							target_data_len);
		break;
	default:
		nfc_dev_err(&dev->interface->dev, "Unknown current poll"
								" modulation");
		return -EPROTO;
	}

	if (rc)
		return rc;

	if (!(nfc_tgt.supported_protocols & dev->poll_protocols)) {
		nfc_dev_dbg(&dev->interface->dev, "The target found does not"
						" have the desired protocol");
		return -EAGAIN;
	}

	nfc_dev_dbg(&dev->interface->dev, "Target found - supported protocols: "
					"0x%x", nfc_tgt.supported_protocols);

	dev->tgt_available_prots = nfc_tgt.supported_protocols;

	nfc_targets_found(dev->nfc_dev, &nfc_tgt, 1);

	return 0;
}

static void pn533_poll_reset_mod_list(struct pn533 *dev)
{
	dev->poll_mod_count = 0;
}

static void pn533_poll_add_mod(struct pn533 *dev, u8 mod_index)
{
	dev->poll_mod_active[dev->poll_mod_count] =
		(struct pn533_poll_modulations *) &poll_mod[mod_index];
	dev->poll_mod_count++;
}

static void pn533_poll_create_mod_list(struct pn533 *dev, u32 protocols)
{
	pn533_poll_reset_mod_list(dev);

	if (protocols & NFC_PROTO_MIFARE_MASK
					|| protocols & NFC_PROTO_ISO14443_MASK
					|| protocols & NFC_PROTO_NFC_DEP_MASK)
		pn533_poll_add_mod(dev, PN533_POLL_MOD_106KBPS_A);

	if (protocols & NFC_PROTO_FELICA_MASK
					|| protocols & NFC_PROTO_NFC_DEP_MASK) {
		pn533_poll_add_mod(dev, PN533_POLL_MOD_212KBPS_FELICA);
		pn533_poll_add_mod(dev, PN533_POLL_MOD_424KBPS_FELICA);
	}

	if (protocols & NFC_PROTO_JEWEL_MASK)
		pn533_poll_add_mod(dev, PN533_POLL_MOD_106KBPS_JEWEL);

	if (protocols & NFC_PROTO_ISO14443_MASK)
		pn533_poll_add_mod(dev, PN533_POLL_MOD_847KBPS_B);
}

static void pn533_start_poll_frame(struct pn533_frame *frame,
					struct pn533_poll_modulations *mod)
{

	pn533_tx_frame_init(frame, PN533_CMD_IN_LIST_PASSIVE_TARGET);

	memcpy(PN533_FRAME_CMD_PARAMS_PTR(frame), &mod->data, mod->len);
	frame->datalen += mod->len;

	pn533_tx_frame_finish(frame);
}

static int pn533_start_poll_complete(struct pn533 *dev, void *arg,
						u8 *params, int params_len)
{
	struct pn533_poll_response *resp;
	struct pn533_poll_modulations *next_mod;
	int rc;

	nfc_dev_dbg(&dev->interface->dev, "%s", __func__);

	if (params_len == -ENOENT) {
		nfc_dev_dbg(&dev->interface->dev, "Polling operation has been"
								" stopped");
		goto stop_poll;
	}

	if (params_len < 0) {
		nfc_dev_err(&dev->interface->dev, "Error %d when running poll",
								params_len);
		goto stop_poll;
	}

	resp = (struct pn533_poll_response *) params;
	if (resp->nbtg) {
		rc = pn533_target_found(dev, resp, params_len);

		/* We must stop the poll after a valid target found */
		if (rc == 0)
			goto stop_poll;

		if (rc != -EAGAIN)
			nfc_dev_err(&dev->interface->dev, "The target found is"
					" not valid - continuing to poll");
	}

	dev->poll_mod_curr = (dev->poll_mod_curr + 1) % dev->poll_mod_count;

	next_mod = dev->poll_mod_active[dev->poll_mod_curr];

	nfc_dev_dbg(&dev->interface->dev, "Polling next modulation (0x%x)",
							dev->poll_mod_curr);

	pn533_start_poll_frame(dev->out_frame, next_mod);

	/* Don't need to down the semaphore again */
	rc = __pn533_send_cmd_frame_async(dev, dev->out_frame, dev->in_frame,
				dev->in_maxlen, pn533_start_poll_complete,
				NULL, GFP_ATOMIC);

	if (rc == -EPERM) {
		nfc_dev_dbg(&dev->interface->dev, "Cannot poll next modulation"
					" because poll has been stopped");
		goto stop_poll;
	}

	if (rc) {
		nfc_dev_err(&dev->interface->dev, "Error %d when trying to poll"
							" next modulation", rc);
		goto stop_poll;
	}

	/* Inform caller function to do not up the semaphore */
	return -EINPROGRESS;

stop_poll:
	pn533_poll_reset_mod_list(dev);
	dev->poll_protocols = 0;
	return 0;
}

static int pn533_start_poll(struct nfc_dev *nfc_dev, u32 protocols)
{
	struct pn533 *dev = nfc_get_drvdata(nfc_dev);
	struct pn533_poll_modulations *start_mod;
	int rc;

	nfc_dev_dbg(&dev->interface->dev, "%s - protocols=0x%x", __func__,
								protocols);

	if (dev->poll_mod_count) {
		nfc_dev_err(&dev->interface->dev, "Polling operation already"
								" active");
		return -EBUSY;
	}

	if (dev->tgt_active_prot) {
		nfc_dev_err(&dev->interface->dev, "Cannot poll with a target"
							" already activated");
		return -EBUSY;
	}

	pn533_poll_create_mod_list(dev, protocols);

	if (!dev->poll_mod_count) {
		nfc_dev_err(&dev->interface->dev, "No valid protocols"
								" specified");
		rc = -EINVAL;
		goto error;
	}

	nfc_dev_dbg(&dev->interface->dev, "It will poll %d modulations types",
							dev->poll_mod_count);

	dev->poll_mod_curr = 0;
	start_mod = dev->poll_mod_active[dev->poll_mod_curr];

	pn533_start_poll_frame(dev->out_frame, start_mod);

	rc = pn533_send_cmd_frame_async(dev, dev->out_frame, dev->in_frame,
				dev->in_maxlen,	pn533_start_poll_complete,
				NULL, GFP_KERNEL);

	if (rc) {
		nfc_dev_err(&dev->interface->dev, "Error %d when trying to"
							" start poll", rc);
		goto error;
	}

	dev->poll_protocols = protocols;

	return 0;

error:
	pn533_poll_reset_mod_list(dev);
	return rc;
}

static void pn533_stop_poll(struct nfc_dev *nfc_dev)
{
	struct pn533 *dev = nfc_get_drvdata(nfc_dev);

	nfc_dev_dbg(&dev->interface->dev, "%s", __func__);

	if (!dev->poll_mod_count) {
		nfc_dev_dbg(&dev->interface->dev, "Polling operation was not"
								" running");
		return;
	}

	/* An ack will cancel the last issued command (poll) */
	pn533_send_ack(dev, GFP_KERNEL);

	/* prevent pn533_start_poll_complete to issue a new poll meanwhile */
	usb_kill_urb(dev->in_urb);
}

static int pn533_activate_target_nfcdep(struct pn533 *dev)
{
	struct pn533_cmd_activate_param param;
	struct pn533_cmd_activate_response *resp;
	u16 gt_len;
	int rc;

	nfc_dev_dbg(&dev->interface->dev, "%s", __func__);

	pn533_tx_frame_init(dev->out_frame, PN533_CMD_IN_ATR);

	param.tg = 1;
	param.next = 0;
	memcpy(PN533_FRAME_CMD_PARAMS_PTR(dev->out_frame), &param,
				sizeof(struct pn533_cmd_activate_param));
	dev->out_frame->datalen += sizeof(struct pn533_cmd_activate_param);

	pn533_tx_frame_finish(dev->out_frame);

	rc = pn533_send_cmd_frame_sync(dev, dev->out_frame, dev->in_frame,
								dev->in_maxlen);
	if (rc)
		return rc;

	resp = (struct pn533_cmd_activate_response *)
				PN533_FRAME_CMD_PARAMS_PTR(dev->in_frame);
	rc = resp->status & PN533_CMD_RET_MASK;
	if (rc != PN533_CMD_RET_SUCCESS)
		return -EIO;

	/* ATR_RES general bytes are located at offset 16 */
	gt_len = PN533_FRAME_CMD_PARAMS_LEN(dev->in_frame) - 16;
	rc = nfc_set_remote_general_bytes(dev->nfc_dev, resp->gt, gt_len);

	return rc;
}

static int pn533_activate_target(struct nfc_dev *nfc_dev, u32 target_idx,
								u32 protocol)
{
	struct pn533 *dev = nfc_get_drvdata(nfc_dev);
	int rc;

	nfc_dev_dbg(&dev->interface->dev, "%s - protocol=%u", __func__,
								protocol);

	if (dev->poll_mod_count) {
		nfc_dev_err(&dev->interface->dev, "Cannot activate while"
								" polling");
		return -EBUSY;
	}

	if (dev->tgt_active_prot) {
		nfc_dev_err(&dev->interface->dev, "There is already an active"
								" target");
		return -EBUSY;
	}

	if (!dev->tgt_available_prots) {
		nfc_dev_err(&dev->interface->dev, "There is no available target"
								" to activate");
		return -EINVAL;
	}

	if (!(dev->tgt_available_prots & (1 << protocol))) {
		nfc_dev_err(&dev->interface->dev, "The target does not support"
					" the requested protocol %u", protocol);
		return -EINVAL;
	}

	if (protocol == NFC_PROTO_NFC_DEP) {
		rc = pn533_activate_target_nfcdep(dev);
		if (rc) {
			nfc_dev_err(&dev->interface->dev, "Error %d when"
						" activating target with"
						" NFC_DEP protocol", rc);
			return rc;
		}
	}

	dev->tgt_active_prot = protocol;
	dev->tgt_available_prots = 0;

	return 0;
}

static void pn533_deactivate_target(struct nfc_dev *nfc_dev, u32 target_idx)
{
	struct pn533 *dev = nfc_get_drvdata(nfc_dev);
	u8 tg;
	u8 status;
	int rc;

	nfc_dev_dbg(&dev->interface->dev, "%s", __func__);

	if (!dev->tgt_active_prot) {
		nfc_dev_err(&dev->interface->dev, "There is no active target");
		return;
	}

	dev->tgt_active_prot = 0;

	pn533_tx_frame_init(dev->out_frame, PN533_CMD_IN_RELEASE);

	tg = 1;
	memcpy(PN533_FRAME_CMD_PARAMS_PTR(dev->out_frame), &tg, sizeof(u8));
	dev->out_frame->datalen += sizeof(u8);

	pn533_tx_frame_finish(dev->out_frame);

	rc = pn533_send_cmd_frame_sync(dev, dev->out_frame, dev->in_frame,
								dev->in_maxlen);
	if (rc) {
		nfc_dev_err(&dev->interface->dev, "Error when sending release"
						" command to the controller");
		return;
	}

	status = PN533_FRAME_CMD_PARAMS_PTR(dev->in_frame)[0];
	rc = status & PN533_CMD_RET_MASK;
	if (rc != PN533_CMD_RET_SUCCESS)
		nfc_dev_err(&dev->interface->dev, "Error 0x%x when releasing"
							" the target", rc);

	return;
}


static int pn533_in_dep_link_up_complete(struct pn533 *dev, void *arg,
						u8 *params, int params_len)
{
	struct pn533_cmd_jump_dep *cmd;
	struct pn533_cmd_jump_dep_response *resp;
	struct nfc_target nfc_target;
	u8 target_gt_len;
	int rc;

	if (params_len == -ENOENT) {
		nfc_dev_dbg(&dev->interface->dev, "");
		return 0;
	}

	if (params_len < 0) {
		nfc_dev_err(&dev->interface->dev,
				"Error %d when bringing DEP link up",
								params_len);
		return 0;
	}

	if (dev->tgt_available_prots &&
	    !(dev->tgt_available_prots & (1 << NFC_PROTO_NFC_DEP))) {
		nfc_dev_err(&dev->interface->dev,
			"The target does not support DEP");
		return -EINVAL;
	}

	resp = (struct pn533_cmd_jump_dep_response *) params;
	cmd = (struct pn533_cmd_jump_dep *) arg;
	rc = resp->status & PN533_CMD_RET_MASK;
	if (rc != PN533_CMD_RET_SUCCESS) {
		nfc_dev_err(&dev->interface->dev,
				"Bringing DEP link up failed %d", rc);
		return 0;
	}

	if (!dev->tgt_available_prots) {
		nfc_dev_dbg(&dev->interface->dev, "Creating new target");

		nfc_target.supported_protocols = NFC_PROTO_NFC_DEP_MASK;
		rc = nfc_targets_found(dev->nfc_dev, &nfc_target, 1);
		if (rc)
			return 0;

		dev->tgt_available_prots = 0;
	}

	dev->tgt_active_prot = NFC_PROTO_NFC_DEP;

	/* ATR_RES general bytes are located at offset 17 */
	target_gt_len = PN533_FRAME_CMD_PARAMS_LEN(dev->in_frame) - 17;
	rc = nfc_set_remote_general_bytes(dev->nfc_dev,
						resp->gt, target_gt_len);
	if (rc == 0)
		rc = nfc_dep_link_is_up(dev->nfc_dev,
						dev->nfc_dev->targets[0].idx,
						!cmd->active, NFC_RF_INITIATOR);

	return 0;
}

static int pn533_dep_link_up(struct nfc_dev *nfc_dev, int target_idx,
						u8 comm_mode, u8 rf_mode)
{
	struct pn533 *dev = nfc_get_drvdata(nfc_dev);
	struct pn533_cmd_jump_dep *cmd;
	u8 cmd_len, local_gt_len, *local_gt;
	int rc;

	nfc_dev_dbg(&dev->interface->dev, "%s", __func__);

	if (rf_mode == NFC_RF_TARGET) {
		nfc_dev_err(&dev->interface->dev, "Target mode not supported");
		return -EOPNOTSUPP;
	}


	if (dev->poll_mod_count) {
		nfc_dev_err(&dev->interface->dev,
				"Cannot bring the DEP link up while polling");
		return -EBUSY;
	}

	if (dev->tgt_active_prot) {
		nfc_dev_err(&dev->interface->dev,
				"There is already an active target");
		return -EBUSY;
	}

	local_gt = nfc_get_local_general_bytes(dev->nfc_dev, &local_gt_len);
	if (local_gt_len > NFC_MAX_GT_LEN)
		return -EINVAL;

	cmd_len = sizeof(struct pn533_cmd_jump_dep) + local_gt_len;
	cmd = kzalloc(cmd_len, GFP_KERNEL);
	if (cmd == NULL)
		return -ENOMEM;

	pn533_tx_frame_init(dev->out_frame, PN533_CMD_IN_JUMP_FOR_DEP);

	cmd->active = !comm_mode;
	cmd->baud = 0;
	if (local_gt != NULL) {
		cmd->next = 4; /* We have some Gi */
		memcpy(cmd->gt, local_gt, local_gt_len);
	} else {
		cmd->next = 0;
	}

	memcpy(PN533_FRAME_CMD_PARAMS_PTR(dev->out_frame), cmd, cmd_len);
	dev->out_frame->datalen += cmd_len;

	pn533_tx_frame_finish(dev->out_frame);

	rc = pn533_send_cmd_frame_async(dev, dev->out_frame, dev->in_frame,
				dev->in_maxlen,	pn533_in_dep_link_up_complete,
				cmd, GFP_KERNEL);
	if (rc)
		goto out;


out:
	kfree(cmd);

	return rc;
}

static int pn533_dep_link_down(struct nfc_dev *nfc_dev)
{
	pn533_deactivate_target(nfc_dev, 0);

	return 0;
}

#define PN533_CMD_DATAEXCH_HEAD_LEN (sizeof(struct pn533_frame) + 3)
#define PN533_CMD_DATAEXCH_DATA_MAXLEN 262

static int pn533_data_exchange_tx_frame(struct pn533 *dev, struct sk_buff *skb)
{
	int payload_len = skb->len;
	struct pn533_frame *out_frame;
	u8 tg;

	nfc_dev_dbg(&dev->interface->dev, "%s - Sending %d bytes", __func__,
								payload_len);

	if (payload_len > PN533_CMD_DATAEXCH_DATA_MAXLEN) {
		/* TODO: Implement support to multi-part data exchange */
		nfc_dev_err(&dev->interface->dev, "Data length greater than the"
						" max allowed: %d",
						PN533_CMD_DATAEXCH_DATA_MAXLEN);
		return -ENOSYS;
	}

	skb_push(skb, PN533_CMD_DATAEXCH_HEAD_LEN);
	out_frame = (struct pn533_frame *) skb->data;

	pn533_tx_frame_init(out_frame, PN533_CMD_IN_DATA_EXCHANGE);

	tg = 1;
	memcpy(PN533_FRAME_CMD_PARAMS_PTR(out_frame), &tg, sizeof(u8));
	out_frame->datalen += sizeof(u8);

	/* The data is already in the out_frame, just update the datalen */
	out_frame->datalen += payload_len;

	pn533_tx_frame_finish(out_frame);
	skb_put(skb, PN533_FRAME_TAIL_SIZE);

	return 0;
}

struct pn533_data_exchange_arg {
	struct sk_buff *skb_resp;
	struct sk_buff *skb_out;
	data_exchange_cb_t cb;
	void *cb_context;
};

static int pn533_data_exchange_complete(struct pn533 *dev, void *_arg,
						u8 *params, int params_len)
{
	struct pn533_data_exchange_arg *arg = _arg;
	struct sk_buff *skb_resp = arg->skb_resp;
	struct pn533_frame *in_frame = (struct pn533_frame *) skb_resp->data;
	int err = 0;
	u8 status;
	u8 cmd_ret;

	nfc_dev_dbg(&dev->interface->dev, "%s", __func__);

	dev_kfree_skb_irq(arg->skb_out);

	if (params_len < 0) { /* error */
		err = params_len;
		goto error;
	}

	skb_put(skb_resp, PN533_FRAME_SIZE(in_frame));

	status = params[0];

	cmd_ret = status & PN533_CMD_RET_MASK;
	if (cmd_ret != PN533_CMD_RET_SUCCESS) {
		nfc_dev_err(&dev->interface->dev, "PN533 reported error %d when"
						" exchanging data", cmd_ret);
		err = -EIO;
		goto error;
	}

	if (status & PN533_CMD_MI_MASK) {
		/* TODO: Implement support to multi-part data exchange */
		nfc_dev_err(&dev->interface->dev, "Multi-part message not yet"
								" supported");
		/* Prevent the other messages from controller */
		pn533_send_ack(dev, GFP_ATOMIC);
		err = -ENOSYS;
		goto error;
	}

	skb_pull(skb_resp, PN533_CMD_DATAEXCH_HEAD_LEN);
	skb_trim(skb_resp, skb_resp->len - PN533_FRAME_TAIL_SIZE);

	arg->cb(arg->cb_context, skb_resp, 0);
	kfree(arg);
	return 0;

error:
	dev_kfree_skb_irq(skb_resp);
	arg->cb(arg->cb_context, NULL, err);
	kfree(arg);
	return 0;
}

static int pn533_data_exchange(struct nfc_dev *nfc_dev, u32 target_idx,
						struct sk_buff *skb,
						data_exchange_cb_t cb,
						void *cb_context)
{
	struct pn533 *dev = nfc_get_drvdata(nfc_dev);
	struct pn533_frame *out_frame, *in_frame;
	struct pn533_data_exchange_arg *arg;
	struct sk_buff *skb_resp;
	int skb_resp_len;
	int rc;

	nfc_dev_dbg(&dev->interface->dev, "%s", __func__);

	if (!dev->tgt_active_prot) {
		nfc_dev_err(&dev->interface->dev, "Cannot exchange data if"
						" there is no active target");
		rc = -EINVAL;
		goto error;
	}

	rc = pn533_data_exchange_tx_frame(dev, skb);
	if (rc)
		goto error;

	skb_resp_len = PN533_CMD_DATAEXCH_HEAD_LEN +
			PN533_CMD_DATAEXCH_DATA_MAXLEN +
			PN533_FRAME_TAIL_SIZE;

	skb_resp = nfc_alloc_recv_skb(skb_resp_len, GFP_KERNEL);
	if (!skb_resp) {
		rc = -ENOMEM;
		goto error;
	}

	in_frame = (struct pn533_frame *) skb_resp->data;
	out_frame = (struct pn533_frame *) skb->data;

	arg = kmalloc(sizeof(struct pn533_data_exchange_arg), GFP_KERNEL);
	if (!arg) {
		rc = -ENOMEM;
		goto free_skb_resp;
	}

	arg->skb_resp = skb_resp;
	arg->skb_out = skb;
	arg->cb = cb;
	arg->cb_context = cb_context;

	rc = pn533_send_cmd_frame_async(dev, out_frame, in_frame, skb_resp_len,
					pn533_data_exchange_complete, arg,
					GFP_KERNEL);
	if (rc) {
		nfc_dev_err(&dev->interface->dev, "Error %d when trying to"
						" perform data_exchange", rc);
		goto free_arg;
	}

	return 0;

free_arg:
	kfree(arg);
free_skb_resp:
	kfree_skb(skb_resp);
error:
	kfree_skb(skb);
	return rc;
}

static int pn533_set_configuration(struct pn533 *dev, u8 cfgitem, u8 *cfgdata,
								u8 cfgdata_len)
{
	int rc;
	u8 *params;

	nfc_dev_dbg(&dev->interface->dev, "%s", __func__);

	pn533_tx_frame_init(dev->out_frame, PN533_CMD_RF_CONFIGURATION);

	params = PN533_FRAME_CMD_PARAMS_PTR(dev->out_frame);
	params[0] = cfgitem;
	memcpy(&params[1], cfgdata, cfgdata_len);
	dev->out_frame->datalen += (1 + cfgdata_len);

	pn533_tx_frame_finish(dev->out_frame);

	rc = pn533_send_cmd_frame_sync(dev, dev->out_frame, dev->in_frame,
								dev->in_maxlen);

	return rc;
}

struct nfc_ops pn533_nfc_ops = {
	.dev_up = NULL,
	.dev_down = NULL,
	.dep_link_up = pn533_dep_link_up,
	.dep_link_down = pn533_dep_link_down,
	.start_poll = pn533_start_poll,
	.stop_poll = pn533_stop_poll,
	.activate_target = pn533_activate_target,
	.deactivate_target = pn533_deactivate_target,
	.data_exchange = pn533_data_exchange,
};

static int pn533_probe(struct usb_interface *interface,
			const struct usb_device_id *id)
{
	struct pn533_fw_version *fw_ver;
	struct pn533 *dev;
	struct usb_host_interface *iface_desc;
	struct usb_endpoint_descriptor *endpoint;
	struct pn533_config_max_retries max_retries;
	int in_endpoint = 0;
	int out_endpoint = 0;
	int rc = -ENOMEM;
	int i;
	u32 protocols;

	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
	if (!dev)
		return -ENOMEM;

	dev->udev = usb_get_dev(interface_to_usbdev(interface));
	dev->interface = interface;
	sema_init(&dev->cmd_lock, 1);

	iface_desc = interface->cur_altsetting;
	for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
		endpoint = &iface_desc->endpoint[i].desc;

		if (!in_endpoint && usb_endpoint_is_bulk_in(endpoint)) {
			dev->in_maxlen = le16_to_cpu(endpoint->wMaxPacketSize);
			in_endpoint = endpoint->bEndpointAddress;
		}

		if (!out_endpoint && usb_endpoint_is_bulk_out(endpoint)) {
			dev->out_maxlen =
				le16_to_cpu(endpoint->wMaxPacketSize);
			out_endpoint = endpoint->bEndpointAddress;
		}
	}

	if (!in_endpoint || !out_endpoint) {
		nfc_dev_err(&interface->dev, "Could not find bulk-in or"
							" bulk-out endpoint");
		rc = -ENODEV;
		goto error;
	}

	dev->in_frame = kmalloc(dev->in_maxlen, GFP_KERNEL);
	dev->in_urb = usb_alloc_urb(0, GFP_KERNEL);
	dev->out_frame = kmalloc(dev->out_maxlen, GFP_KERNEL);
	dev->out_urb = usb_alloc_urb(0, GFP_KERNEL);

	if (!dev->in_frame || !dev->out_frame ||
		!dev->in_urb || !dev->out_urb)
		goto error;

	usb_fill_bulk_urb(dev->in_urb, dev->udev,
			usb_rcvbulkpipe(dev->udev, in_endpoint),
			NULL, 0, NULL, dev);
	usb_fill_bulk_urb(dev->out_urb, dev->udev,
			usb_sndbulkpipe(dev->udev, out_endpoint),
			NULL, 0,
			pn533_send_complete, dev);

	tasklet_init(&dev->tasklet, pn533_tasklet_cmd_complete, (ulong)dev);

	usb_set_intfdata(interface, dev);

	pn533_tx_frame_init(dev->out_frame, PN533_CMD_GET_FIRMWARE_VERSION);
	pn533_tx_frame_finish(dev->out_frame);

	rc = pn533_send_cmd_frame_sync(dev, dev->out_frame, dev->in_frame,
								dev->in_maxlen);
	if (rc)
		goto kill_tasklet;

	fw_ver = (struct pn533_fw_version *)
				PN533_FRAME_CMD_PARAMS_PTR(dev->in_frame);
	nfc_dev_info(&dev->interface->dev, "NXP PN533 firmware ver %d.%d now"
					" attached", fw_ver->ver, fw_ver->rev);

	protocols = NFC_PROTO_JEWEL_MASK
			| NFC_PROTO_MIFARE_MASK | NFC_PROTO_FELICA_MASK
			| NFC_PROTO_ISO14443_MASK
			| NFC_PROTO_NFC_DEP_MASK;

	dev->nfc_dev = nfc_allocate_device(&pn533_nfc_ops, protocols,
					   PN533_CMD_DATAEXCH_HEAD_LEN,
					   PN533_FRAME_TAIL_SIZE);
	if (!dev->nfc_dev)
		goto kill_tasklet;

	nfc_set_parent_dev(dev->nfc_dev, &interface->dev);
	nfc_set_drvdata(dev->nfc_dev, dev);

	rc = nfc_register_device(dev->nfc_dev);
	if (rc)
		goto free_nfc_dev;

	max_retries.mx_rty_atr = PN533_CONFIG_MAX_RETRIES_ENDLESS;
	max_retries.mx_rty_psl = 2;
	max_retries.mx_rty_passive_act = PN533_CONFIG_MAX_RETRIES_NO_RETRY;

	rc = pn533_set_configuration(dev, PN533_CFGITEM_MAX_RETRIES,
				(u8 *) &max_retries, sizeof(max_retries));

	if (rc) {
		nfc_dev_err(&dev->interface->dev, "Error on setting MAX_RETRIES"
								" config");
		goto free_nfc_dev;
	}

	return 0;

free_nfc_dev:
	nfc_free_device(dev->nfc_dev);
kill_tasklet:
	tasklet_kill(&dev->tasklet);
error:
	kfree(dev->in_frame);
	usb_free_urb(dev->in_urb);
	kfree(dev->out_frame);
	usb_free_urb(dev->out_urb);
	kfree(dev);
	return rc;
}

static void pn533_disconnect(struct usb_interface *interface)
{
	struct pn533 *dev;

	dev = usb_get_intfdata(interface);
	usb_set_intfdata(interface, NULL);

	nfc_unregister_device(dev->nfc_dev);
	nfc_free_device(dev->nfc_dev);

	usb_kill_urb(dev->in_urb);
	usb_kill_urb(dev->out_urb);

	tasklet_kill(&dev->tasklet);

	kfree(dev->in_frame);
	usb_free_urb(dev->in_urb);
	kfree(dev->out_frame);
	usb_free_urb(dev->out_urb);
	kfree(dev);

	nfc_dev_info(&interface->dev, "NXP PN533 NFC device disconnected");
}

static struct usb_driver pn533_driver = {
	.name =		"pn533",
	.probe =	pn533_probe,
	.disconnect =	pn533_disconnect,
	.id_table =	pn533_table,
};

module_usb_driver(pn533_driver);

MODULE_AUTHOR("Lauro Ramos Venancio <lauro.venancio@openbossa.org>,"
			" Aloisio Almeida Jr <aloisio.almeida@openbossa.org>");
MODULE_DESCRIPTION("PN533 usb driver ver " VERSION);
MODULE_VERSION(VERSION);
MODULE_LICENSE("GPL");
OpenPOWER on IntegriCloud