pn533.c 38.5 KB
Newer Older
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
/*
 * 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>
31
#include <net/nfc/nfc.h>
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

#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_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;


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;
	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;

	return 0;
}

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;
}

#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;
}

1342
static int pn533_data_exchange(struct nfc_dev *nfc_dev, u32 target_idx,
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
						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_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 = {
1435 1436
	.dev_up = NULL,
	.dev_down = NULL,
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
	.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;

1528 1529 1530
	dev->nfc_dev = nfc_allocate_device(&pn533_nfc_ops, protocols,
					   PN533_CMD_DATAEXCH_HEAD_LEN,
					   PN533_FRAME_TAIL_SIZE);
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
	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);

1590
	nfc_dev_info(&interface->dev, "NXP PN533 NFC device disconnected");
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
}

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

static int __init pn533_init(void)
{
	int rc;

	rc = usb_register(&pn533_driver);
	if (rc)
		err("usb_register failed. Error number %d", rc);

	return rc;
}

static void __exit pn533_exit(void)
{
	usb_deregister(&pn533_driver);
}

module_init(pn533_init);
module_exit(pn533_exit);

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");