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v4.10.11
 
   1/*
   2 * NFC Digital Protocol stack
   3 * Copyright (c) 2013, Intel Corporation.
   4 *
   5 * This program is free software; you can redistribute it and/or modify it
   6 * under the terms and conditions of the GNU General Public License,
   7 * version 2, as published by the Free Software Foundation.
   8 *
   9 * This program is distributed in the hope it will be useful, but WITHOUT
  10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12 * more details.
  13 *
  14 */
  15
  16#define pr_fmt(fmt) "digital: %s: " fmt, __func__
  17
  18#include "digital.h"
  19
  20#define DIGITAL_NFC_DEP_N_RETRY_NACK	2
  21#define DIGITAL_NFC_DEP_N_RETRY_ATN	2
  22
  23#define DIGITAL_NFC_DEP_FRAME_DIR_OUT 0xD4
  24#define DIGITAL_NFC_DEP_FRAME_DIR_IN  0xD5
  25
  26#define DIGITAL_NFC_DEP_NFCA_SOD_SB   0xF0
  27
  28#define DIGITAL_CMD_ATR_REQ 0x00
  29#define DIGITAL_CMD_ATR_RES 0x01
  30#define DIGITAL_CMD_PSL_REQ 0x04
  31#define DIGITAL_CMD_PSL_RES 0x05
  32#define DIGITAL_CMD_DEP_REQ 0x06
  33#define DIGITAL_CMD_DEP_RES 0x07
  34
  35#define DIGITAL_ATR_REQ_MIN_SIZE 16
  36#define DIGITAL_ATR_REQ_MAX_SIZE 64
  37
  38#define DIGITAL_ATR_RES_TO_WT(s)	((s) & 0xF)
  39
  40#define DIGITAL_DID_MAX	14
  41
  42#define DIGITAL_PAYLOAD_SIZE_MAX	254
  43#define DIGITAL_PAYLOAD_BITS_TO_PP(s)	(((s) & 0x3) << 4)
  44#define DIGITAL_PAYLOAD_PP_TO_BITS(s)	(((s) >> 4) & 0x3)
  45#define DIGITAL_PAYLOAD_BITS_TO_FSL(s)	((s) & 0x3)
  46#define DIGITAL_PAYLOAD_FSL_TO_BITS(s)	((s) & 0x3)
  47
  48#define DIGITAL_GB_BIT	0x02
  49
  50#define DIGITAL_NFC_DEP_REQ_RES_HEADROOM	2 /* SoD: [SB (NFC-A)] + LEN */
  51#define DIGITAL_NFC_DEP_REQ_RES_TAILROOM	2 /* EoD: 2-byte CRC */
  52
  53#define DIGITAL_NFC_DEP_PFB_TYPE(pfb) ((pfb) & 0xE0)
  54
  55#define DIGITAL_NFC_DEP_PFB_TIMEOUT_BIT 0x10
  56#define DIGITAL_NFC_DEP_PFB_MI_BIT	0x10
  57#define DIGITAL_NFC_DEP_PFB_NACK_BIT	0x10
  58#define DIGITAL_NFC_DEP_PFB_DID_BIT	0x04
  59
  60#define DIGITAL_NFC_DEP_PFB_IS_TIMEOUT(pfb) \
  61				((pfb) & DIGITAL_NFC_DEP_PFB_TIMEOUT_BIT)
  62#define DIGITAL_NFC_DEP_MI_BIT_SET(pfb)  ((pfb) & DIGITAL_NFC_DEP_PFB_MI_BIT)
  63#define DIGITAL_NFC_DEP_NACK_BIT_SET(pfb) ((pfb) & DIGITAL_NFC_DEP_PFB_NACK_BIT)
  64#define DIGITAL_NFC_DEP_NAD_BIT_SET(pfb) ((pfb) & 0x08)
  65#define DIGITAL_NFC_DEP_DID_BIT_SET(pfb) ((pfb) & DIGITAL_NFC_DEP_PFB_DID_BIT)
  66#define DIGITAL_NFC_DEP_PFB_PNI(pfb)     ((pfb) & 0x03)
  67
  68#define DIGITAL_NFC_DEP_RTOX_VALUE(data) ((data) & 0x3F)
  69#define DIGITAL_NFC_DEP_RTOX_MAX	 59
  70
  71#define DIGITAL_NFC_DEP_PFB_I_PDU          0x00
  72#define DIGITAL_NFC_DEP_PFB_ACK_NACK_PDU   0x40
  73#define DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU 0x80
  74
  75struct digital_atr_req {
  76	u8 dir;
  77	u8 cmd;
  78	u8 nfcid3[10];
  79	u8 did;
  80	u8 bs;
  81	u8 br;
  82	u8 pp;
  83	u8 gb[0];
  84} __packed;
  85
  86struct digital_atr_res {
  87	u8 dir;
  88	u8 cmd;
  89	u8 nfcid3[10];
  90	u8 did;
  91	u8 bs;
  92	u8 br;
  93	u8 to;
  94	u8 pp;
  95	u8 gb[0];
  96} __packed;
  97
  98struct digital_psl_req {
  99	u8 dir;
 100	u8 cmd;
 101	u8 did;
 102	u8 brs;
 103	u8 fsl;
 104} __packed;
 105
 106struct digital_psl_res {
 107	u8 dir;
 108	u8 cmd;
 109	u8 did;
 110} __packed;
 111
 112struct digital_dep_req_res {
 113	u8 dir;
 114	u8 cmd;
 115	u8 pfb;
 116} __packed;
 117
 118static void digital_in_recv_dep_res(struct nfc_digital_dev *ddev, void *arg,
 119				    struct sk_buff *resp);
 120static void digital_tg_recv_dep_req(struct nfc_digital_dev *ddev, void *arg,
 121				    struct sk_buff *resp);
 122
 123static const u8 digital_payload_bits_map[4] = {
 124	[0] = 64,
 125	[1] = 128,
 126	[2] = 192,
 127	[3] = 254
 128};
 129
 130/* Response Waiting Time for ATR_RES PDU in ms
 131 *
 132 * RWT(ATR_RES) = RWT(nfcdep,activation) + dRWT(nfcdep) + dT(nfcdep,initiator)
 133 *
 134 * with:
 135 *  RWT(nfcdep,activation) = 4096 * 2^12 / f(c) s
 136 *  dRWT(nfcdep) = 16 / f(c) s
 137 *  dT(nfcdep,initiator) = 100 ms
 138 *  f(c) = 13560000 Hz
 139 */
 140#define DIGITAL_ATR_RES_RWT 1337
 141
 142/* Response Waiting Time for other DEP PDUs in ms
 143 *
 144 * max_rwt = rwt + dRWT(nfcdep) + dT(nfcdep,initiator)
 145 *
 146 * with:
 147 *  rwt = (256 * 16 / f(c)) * 2^wt s
 148 *  dRWT(nfcdep) = 16 / f(c) s
 149 *  dT(nfcdep,initiator) = 100 ms
 150 *  f(c) = 13560000 Hz
 151 *  0 <= wt <= 14 (given by the target by the TO field of ATR_RES response)
 152 */
 153#define DIGITAL_NFC_DEP_IN_MAX_WT 14
 154#define DIGITAL_NFC_DEP_TG_MAX_WT 8
 155static const u16 digital_rwt_map[DIGITAL_NFC_DEP_IN_MAX_WT + 1] = {
 156	100,  101,  101,  102,  105,
 157	110,  119,  139,  177,  255,
 158	409,  719, 1337, 2575, 5049,
 159};
 160
 161static u8 digital_payload_bits_to_size(u8 payload_bits)
 162{
 163	if (payload_bits >= ARRAY_SIZE(digital_payload_bits_map))
 164		return 0;
 165
 166	return digital_payload_bits_map[payload_bits];
 167}
 168
 169static u8 digital_payload_size_to_bits(u8 payload_size)
 170{
 171	int i;
 172
 173	for (i = 0; i < ARRAY_SIZE(digital_payload_bits_map); i++)
 174		if (digital_payload_bits_map[i] == payload_size)
 175			return i;
 176
 177	return 0xff;
 178}
 179
 180static void digital_skb_push_dep_sod(struct nfc_digital_dev *ddev,
 181				     struct sk_buff *skb)
 182{
 183	skb_push(skb, sizeof(u8));
 184
 185	skb->data[0] = skb->len;
 186
 187	if (ddev->curr_rf_tech == NFC_DIGITAL_RF_TECH_106A)
 188		*skb_push(skb, sizeof(u8)) = DIGITAL_NFC_DEP_NFCA_SOD_SB;
 189}
 190
 191static int digital_skb_pull_dep_sod(struct nfc_digital_dev *ddev,
 192				    struct sk_buff *skb)
 193{
 194	u8 size;
 195
 196	if (skb->len < 2)
 197		return -EIO;
 198
 199	if (ddev->curr_rf_tech == NFC_DIGITAL_RF_TECH_106A)
 200		skb_pull(skb, sizeof(u8));
 201
 202	size = skb->data[0];
 203	if (size != skb->len)
 204		return -EIO;
 205
 206	skb_pull(skb, sizeof(u8));
 207
 208	return 0;
 209}
 210
 211static struct sk_buff *
 212digital_send_dep_data_prep(struct nfc_digital_dev *ddev, struct sk_buff *skb,
 213			   struct digital_dep_req_res *dep_req_res,
 214			   struct digital_data_exch *data_exch)
 215{
 216	struct sk_buff *new_skb;
 217
 218	if (skb->len > ddev->remote_payload_max) {
 219		dep_req_res->pfb |= DIGITAL_NFC_DEP_PFB_MI_BIT;
 220
 221		new_skb = digital_skb_alloc(ddev, ddev->remote_payload_max);
 222		if (!new_skb) {
 223			kfree_skb(ddev->chaining_skb);
 224			ddev->chaining_skb = NULL;
 225
 226			return ERR_PTR(-ENOMEM);
 227		}
 228
 229		memcpy(skb_put(new_skb, ddev->remote_payload_max), skb->data,
 230		       ddev->remote_payload_max);
 231		skb_pull(skb, ddev->remote_payload_max);
 232
 233		ddev->chaining_skb = skb;
 234		ddev->data_exch = data_exch;
 235	} else {
 236		ddev->chaining_skb = NULL;
 237		new_skb = skb;
 238	}
 239
 240	return new_skb;
 241}
 242
 243static struct sk_buff *
 244digital_recv_dep_data_gather(struct nfc_digital_dev *ddev, u8 pfb,
 245			     struct sk_buff *resp,
 246			     int (*send_ack)(struct nfc_digital_dev *ddev,
 247					     struct digital_data_exch
 248							     *data_exch),
 249			     struct digital_data_exch *data_exch)
 250{
 251	struct sk_buff *new_skb;
 252	int rc;
 253
 254	if (DIGITAL_NFC_DEP_MI_BIT_SET(pfb) && (!ddev->chaining_skb)) {
 255		ddev->chaining_skb =
 256			nfc_alloc_recv_skb(8 * ddev->local_payload_max,
 257					   GFP_KERNEL);
 258		if (!ddev->chaining_skb) {
 259			rc = -ENOMEM;
 260			goto error;
 261		}
 262	}
 263
 264	if (ddev->chaining_skb) {
 265		if (resp->len > skb_tailroom(ddev->chaining_skb)) {
 266			new_skb = skb_copy_expand(ddev->chaining_skb,
 267						  skb_headroom(
 268							  ddev->chaining_skb),
 269						  8 * ddev->local_payload_max,
 270						  GFP_KERNEL);
 271			if (!new_skb) {
 272				rc = -ENOMEM;
 273				goto error;
 274			}
 275
 276			kfree_skb(ddev->chaining_skb);
 277			ddev->chaining_skb = new_skb;
 278		}
 279
 280		memcpy(skb_put(ddev->chaining_skb, resp->len), resp->data,
 281		       resp->len);
 282
 283		kfree_skb(resp);
 284		resp = NULL;
 285
 286		if (DIGITAL_NFC_DEP_MI_BIT_SET(pfb)) {
 287			rc = send_ack(ddev, data_exch);
 288			if (rc)
 289				goto error;
 290
 291			return NULL;
 292		}
 293
 294		resp = ddev->chaining_skb;
 295		ddev->chaining_skb = NULL;
 296	}
 297
 298	return resp;
 299
 300error:
 301	kfree_skb(resp);
 302
 303	kfree_skb(ddev->chaining_skb);
 304	ddev->chaining_skb = NULL;
 305
 306	return ERR_PTR(rc);
 307}
 308
 309static void digital_in_recv_psl_res(struct nfc_digital_dev *ddev, void *arg,
 310				    struct sk_buff *resp)
 311{
 312	struct nfc_target *target = arg;
 313	struct digital_psl_res *psl_res;
 314	int rc;
 315
 316	if (IS_ERR(resp)) {
 317		rc = PTR_ERR(resp);
 318		resp = NULL;
 319		goto exit;
 320	}
 321
 322	rc = ddev->skb_check_crc(resp);
 323	if (rc) {
 324		PROTOCOL_ERR("14.4.1.6");
 325		goto exit;
 326	}
 327
 328	rc = digital_skb_pull_dep_sod(ddev, resp);
 329	if (rc) {
 330		PROTOCOL_ERR("14.4.1.2");
 331		goto exit;
 332	}
 333
 334	psl_res = (struct digital_psl_res *)resp->data;
 335
 336	if ((resp->len != sizeof(*psl_res)) ||
 337	    (psl_res->dir != DIGITAL_NFC_DEP_FRAME_DIR_IN) ||
 338	    (psl_res->cmd != DIGITAL_CMD_PSL_RES)) {
 339		rc = -EIO;
 340		goto exit;
 341	}
 342
 343	rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH,
 344				     NFC_DIGITAL_RF_TECH_424F);
 345	if (rc)
 346		goto exit;
 347
 348	rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
 349				     NFC_DIGITAL_FRAMING_NFCF_NFC_DEP);
 350	if (rc)
 351		goto exit;
 352
 353	if (!DIGITAL_DRV_CAPS_IN_CRC(ddev) &&
 354	    (ddev->curr_rf_tech == NFC_DIGITAL_RF_TECH_106A)) {
 355		ddev->skb_add_crc = digital_skb_add_crc_f;
 356		ddev->skb_check_crc = digital_skb_check_crc_f;
 357	}
 358
 359	ddev->curr_rf_tech = NFC_DIGITAL_RF_TECH_424F;
 360
 361	nfc_dep_link_is_up(ddev->nfc_dev, target->idx, NFC_COMM_ACTIVE,
 362			   NFC_RF_INITIATOR);
 363
 364	ddev->curr_nfc_dep_pni = 0;
 365
 366exit:
 367	dev_kfree_skb(resp);
 368
 369	if (rc)
 370		ddev->curr_protocol = 0;
 371}
 372
 373static int digital_in_send_psl_req(struct nfc_digital_dev *ddev,
 374				   struct nfc_target *target)
 375{
 376	struct sk_buff *skb;
 377	struct digital_psl_req *psl_req;
 378	int rc;
 379	u8 payload_size, payload_bits;
 380
 381	skb = digital_skb_alloc(ddev, sizeof(*psl_req));
 382	if (!skb)
 383		return -ENOMEM;
 384
 385	skb_put(skb, sizeof(*psl_req));
 386
 387	psl_req = (struct digital_psl_req *)skb->data;
 388
 389	psl_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT;
 390	psl_req->cmd = DIGITAL_CMD_PSL_REQ;
 391	psl_req->did = 0;
 392	psl_req->brs = (0x2 << 3) | 0x2; /* 424F both directions */
 393
 394	payload_size = min(ddev->local_payload_max, ddev->remote_payload_max);
 395	payload_bits = digital_payload_size_to_bits(payload_size);
 396	psl_req->fsl = DIGITAL_PAYLOAD_BITS_TO_FSL(payload_bits);
 397
 398	ddev->local_payload_max = payload_size;
 399	ddev->remote_payload_max = payload_size;
 400
 401	digital_skb_push_dep_sod(ddev, skb);
 402
 403	ddev->skb_add_crc(skb);
 404
 405	rc = digital_in_send_cmd(ddev, skb, ddev->dep_rwt,
 406				 digital_in_recv_psl_res, target);
 407	if (rc)
 408		kfree_skb(skb);
 409
 410	return rc;
 411}
 412
 413static void digital_in_recv_atr_res(struct nfc_digital_dev *ddev, void *arg,
 414				 struct sk_buff *resp)
 415{
 416	struct nfc_target *target = arg;
 417	struct digital_atr_res *atr_res;
 418	u8 gb_len, payload_bits;
 419	u8 wt;
 420	int rc;
 421
 422	if (IS_ERR(resp)) {
 423		rc = PTR_ERR(resp);
 424		resp = NULL;
 425		goto exit;
 426	}
 427
 428	rc = ddev->skb_check_crc(resp);
 429	if (rc) {
 430		PROTOCOL_ERR("14.4.1.6");
 431		goto exit;
 432	}
 433
 434	rc = digital_skb_pull_dep_sod(ddev, resp);
 435	if (rc) {
 436		PROTOCOL_ERR("14.4.1.2");
 437		goto exit;
 438	}
 439
 440	if (resp->len < sizeof(struct digital_atr_res)) {
 441		rc = -EIO;
 442		goto exit;
 443	}
 444
 445	gb_len = resp->len - sizeof(struct digital_atr_res);
 446
 447	atr_res = (struct digital_atr_res *)resp->data;
 448
 449	wt = DIGITAL_ATR_RES_TO_WT(atr_res->to);
 450	if (wt > DIGITAL_NFC_DEP_IN_MAX_WT)
 451		wt = DIGITAL_NFC_DEP_IN_MAX_WT;
 452	ddev->dep_rwt = digital_rwt_map[wt];
 453
 454	payload_bits = DIGITAL_PAYLOAD_PP_TO_BITS(atr_res->pp);
 455	ddev->remote_payload_max = digital_payload_bits_to_size(payload_bits);
 456
 457	if (!ddev->remote_payload_max) {
 458		rc = -EINVAL;
 459		goto exit;
 460	}
 461
 462	rc = nfc_set_remote_general_bytes(ddev->nfc_dev, atr_res->gb, gb_len);
 463	if (rc)
 464		goto exit;
 465
 466	if ((ddev->protocols & NFC_PROTO_FELICA_MASK) &&
 467	    (ddev->curr_rf_tech != NFC_DIGITAL_RF_TECH_424F)) {
 468		rc = digital_in_send_psl_req(ddev, target);
 469		if (!rc)
 470			goto exit;
 471	}
 472
 473	rc = nfc_dep_link_is_up(ddev->nfc_dev, target->idx, NFC_COMM_ACTIVE,
 474				NFC_RF_INITIATOR);
 475
 476	ddev->curr_nfc_dep_pni = 0;
 477
 478exit:
 479	dev_kfree_skb(resp);
 480
 481	if (rc)
 482		ddev->curr_protocol = 0;
 483}
 484
 485int digital_in_send_atr_req(struct nfc_digital_dev *ddev,
 486			    struct nfc_target *target, __u8 comm_mode, __u8 *gb,
 487			    size_t gb_len)
 488{
 489	struct sk_buff *skb;
 490	struct digital_atr_req *atr_req;
 491	uint size;
 492	int rc;
 493	u8 payload_bits;
 494
 495	size = DIGITAL_ATR_REQ_MIN_SIZE + gb_len;
 496
 497	if (size > DIGITAL_ATR_REQ_MAX_SIZE) {
 498		PROTOCOL_ERR("14.6.1.1");
 499		return -EINVAL;
 500	}
 501
 502	skb = digital_skb_alloc(ddev, size);
 503	if (!skb)
 504		return -ENOMEM;
 505
 506	skb_put(skb, sizeof(struct digital_atr_req));
 507
 508	atr_req = (struct digital_atr_req *)skb->data;
 509	memset(atr_req, 0, sizeof(struct digital_atr_req));
 510
 511	atr_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT;
 512	atr_req->cmd = DIGITAL_CMD_ATR_REQ;
 513	if (target->nfcid2_len)
 514		memcpy(atr_req->nfcid3, target->nfcid2, NFC_NFCID2_MAXSIZE);
 515	else
 516		get_random_bytes(atr_req->nfcid3, NFC_NFCID3_MAXSIZE);
 517
 518	atr_req->did = 0;
 519	atr_req->bs = 0;
 520	atr_req->br = 0;
 521
 522	ddev->local_payload_max = DIGITAL_PAYLOAD_SIZE_MAX;
 523	payload_bits = digital_payload_size_to_bits(ddev->local_payload_max);
 524	atr_req->pp = DIGITAL_PAYLOAD_BITS_TO_PP(payload_bits);
 525
 526	if (gb_len) {
 527		atr_req->pp |= DIGITAL_GB_BIT;
 528		memcpy(skb_put(skb, gb_len), gb, gb_len);
 529	}
 530
 531	digital_skb_push_dep_sod(ddev, skb);
 532
 533	ddev->skb_add_crc(skb);
 534
 535	rc = digital_in_send_cmd(ddev, skb, DIGITAL_ATR_RES_RWT,
 536				 digital_in_recv_atr_res, target);
 537	if (rc)
 538		kfree_skb(skb);
 539
 540	return rc;
 541}
 542
 543static int digital_in_send_ack(struct nfc_digital_dev *ddev,
 544			       struct digital_data_exch *data_exch)
 545{
 546	struct digital_dep_req_res *dep_req;
 547	struct sk_buff *skb;
 548	int rc;
 549
 550	skb = digital_skb_alloc(ddev, 1);
 551	if (!skb)
 552		return -ENOMEM;
 553
 554	skb_push(skb, sizeof(struct digital_dep_req_res));
 555
 556	dep_req = (struct digital_dep_req_res *)skb->data;
 557
 558	dep_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT;
 559	dep_req->cmd = DIGITAL_CMD_DEP_REQ;
 560	dep_req->pfb = DIGITAL_NFC_DEP_PFB_ACK_NACK_PDU |
 561		       ddev->curr_nfc_dep_pni;
 562
 563	digital_skb_push_dep_sod(ddev, skb);
 564
 565	ddev->skb_add_crc(skb);
 566
 567	ddev->saved_skb = pskb_copy(skb, GFP_KERNEL);
 568
 569	rc = digital_in_send_cmd(ddev, skb, ddev->dep_rwt,
 570				 digital_in_recv_dep_res, data_exch);
 571	if (rc) {
 572		kfree_skb(skb);
 573		kfree_skb(ddev->saved_skb);
 574		ddev->saved_skb = NULL;
 575	}
 576
 577	return rc;
 578}
 579
 580static int digital_in_send_nack(struct nfc_digital_dev *ddev,
 581				struct digital_data_exch *data_exch)
 582{
 583	struct digital_dep_req_res *dep_req;
 584	struct sk_buff *skb;
 585	int rc;
 586
 587	skb = digital_skb_alloc(ddev, 1);
 588	if (!skb)
 589		return -ENOMEM;
 590
 591	skb_push(skb, sizeof(struct digital_dep_req_res));
 592
 593	dep_req = (struct digital_dep_req_res *)skb->data;
 594
 595	dep_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT;
 596	dep_req->cmd = DIGITAL_CMD_DEP_REQ;
 597	dep_req->pfb = DIGITAL_NFC_DEP_PFB_ACK_NACK_PDU |
 598		       DIGITAL_NFC_DEP_PFB_NACK_BIT | ddev->curr_nfc_dep_pni;
 599
 600	digital_skb_push_dep_sod(ddev, skb);
 601
 602	ddev->skb_add_crc(skb);
 603
 604	rc = digital_in_send_cmd(ddev, skb, ddev->dep_rwt,
 605				 digital_in_recv_dep_res, data_exch);
 606	if (rc)
 607		kfree_skb(skb);
 608
 609	return rc;
 610}
 611
 612static int digital_in_send_atn(struct nfc_digital_dev *ddev,
 613			       struct digital_data_exch *data_exch)
 614{
 615	struct digital_dep_req_res *dep_req;
 616	struct sk_buff *skb;
 617	int rc;
 618
 619	skb = digital_skb_alloc(ddev, 1);
 620	if (!skb)
 621		return -ENOMEM;
 622
 623	skb_push(skb, sizeof(struct digital_dep_req_res));
 624
 625	dep_req = (struct digital_dep_req_res *)skb->data;
 626
 627	dep_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT;
 628	dep_req->cmd = DIGITAL_CMD_DEP_REQ;
 629	dep_req->pfb = DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU;
 630
 631	digital_skb_push_dep_sod(ddev, skb);
 632
 633	ddev->skb_add_crc(skb);
 634
 635	rc = digital_in_send_cmd(ddev, skb, ddev->dep_rwt,
 636				 digital_in_recv_dep_res, data_exch);
 637	if (rc)
 638		kfree_skb(skb);
 639
 640	return rc;
 641}
 642
 643static int digital_in_send_rtox(struct nfc_digital_dev *ddev,
 644				struct digital_data_exch *data_exch, u8 rtox)
 645{
 646	struct digital_dep_req_res *dep_req;
 647	struct sk_buff *skb;
 648	int rc;
 649	u16 rwt_int;
 650
 651	rwt_int = ddev->dep_rwt * rtox;
 652	if (rwt_int > digital_rwt_map[DIGITAL_NFC_DEP_IN_MAX_WT])
 653		rwt_int = digital_rwt_map[DIGITAL_NFC_DEP_IN_MAX_WT];
 654
 655	skb = digital_skb_alloc(ddev, 1);
 656	if (!skb)
 657		return -ENOMEM;
 658
 659	*skb_put(skb, 1) = rtox;
 660
 661	skb_push(skb, sizeof(struct digital_dep_req_res));
 662
 663	dep_req = (struct digital_dep_req_res *)skb->data;
 664
 665	dep_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT;
 666	dep_req->cmd = DIGITAL_CMD_DEP_REQ;
 667	dep_req->pfb = DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU |
 668		       DIGITAL_NFC_DEP_PFB_TIMEOUT_BIT;
 669
 670	digital_skb_push_dep_sod(ddev, skb);
 671
 672	ddev->skb_add_crc(skb);
 673
 674	rc = digital_in_send_cmd(ddev, skb, rwt_int,
 675				 digital_in_recv_dep_res, data_exch);
 676	if (rc)
 677		kfree_skb(skb);
 678
 679	return rc;
 680}
 681
 682static int digital_in_send_saved_skb(struct nfc_digital_dev *ddev,
 683				     struct digital_data_exch *data_exch)
 684{
 685	int rc;
 686
 687	if (!ddev->saved_skb)
 688		return -EINVAL;
 689
 690	skb_get(ddev->saved_skb);
 691
 692	rc = digital_in_send_cmd(ddev, ddev->saved_skb, ddev->dep_rwt,
 693				 digital_in_recv_dep_res, data_exch);
 694	if (rc)
 695		kfree_skb(ddev->saved_skb);
 696
 697	return rc;
 698}
 699
 700static void digital_in_recv_dep_res(struct nfc_digital_dev *ddev, void *arg,
 701				    struct sk_buff *resp)
 702{
 703	struct digital_data_exch *data_exch = arg;
 704	struct digital_dep_req_res *dep_res;
 705	u8 pfb;
 706	uint size;
 707	int rc;
 708	u8 rtox;
 709
 710	if (IS_ERR(resp)) {
 711		rc = PTR_ERR(resp);
 712		resp = NULL;
 713
 714		if ((rc == -EIO || (rc == -ETIMEDOUT && ddev->nack_count)) &&
 715		    (ddev->nack_count++ < DIGITAL_NFC_DEP_N_RETRY_NACK)) {
 716			ddev->atn_count = 0;
 717
 718			rc = digital_in_send_nack(ddev, data_exch);
 719			if (rc)
 720				goto error;
 721
 722			return;
 723		} else if ((rc == -ETIMEDOUT) &&
 724			   (ddev->atn_count++ < DIGITAL_NFC_DEP_N_RETRY_ATN)) {
 725			ddev->nack_count = 0;
 726
 727			rc = digital_in_send_atn(ddev, data_exch);
 728			if (rc)
 729				goto error;
 730
 731			return;
 732		}
 733
 734		goto exit;
 735	}
 736
 737	rc = digital_skb_pull_dep_sod(ddev, resp);
 738	if (rc) {
 739		PROTOCOL_ERR("14.4.1.2");
 740		goto exit;
 741	}
 742
 743	rc = ddev->skb_check_crc(resp);
 744	if (rc) {
 745		if ((resp->len >= 4) &&
 746		    (ddev->nack_count++ < DIGITAL_NFC_DEP_N_RETRY_NACK)) {
 747			ddev->atn_count = 0;
 748
 749			rc = digital_in_send_nack(ddev, data_exch);
 750			if (rc)
 751				goto error;
 752
 753			kfree_skb(resp);
 754
 755			return;
 756		}
 757
 758		PROTOCOL_ERR("14.4.1.6");
 759		goto error;
 760	}
 761
 762	ddev->atn_count = 0;
 763	ddev->nack_count = 0;
 764
 765	if (resp->len > ddev->local_payload_max) {
 766		rc = -EMSGSIZE;
 767		goto exit;
 768	}
 769
 770	size = sizeof(struct digital_dep_req_res);
 771	dep_res = (struct digital_dep_req_res *)resp->data;
 772
 773	if (resp->len < size || dep_res->dir != DIGITAL_NFC_DEP_FRAME_DIR_IN ||
 774	    dep_res->cmd != DIGITAL_CMD_DEP_RES) {
 775		rc = -EIO;
 776		goto error;
 777	}
 778
 779	pfb = dep_res->pfb;
 780
 781	if (DIGITAL_NFC_DEP_DID_BIT_SET(pfb)) {
 782		PROTOCOL_ERR("14.8.2.1");
 783		rc = -EIO;
 784		goto error;
 785	}
 786
 787	if (DIGITAL_NFC_DEP_NAD_BIT_SET(pfb)) {
 788		rc = -EIO;
 789		goto exit;
 790	}
 791
 792	if (size > resp->len) {
 793		rc = -EIO;
 794		goto error;
 795	}
 796
 797	skb_pull(resp, size);
 798
 799	switch (DIGITAL_NFC_DEP_PFB_TYPE(pfb)) {
 800	case DIGITAL_NFC_DEP_PFB_I_PDU:
 801		if (DIGITAL_NFC_DEP_PFB_PNI(pfb) != ddev->curr_nfc_dep_pni) {
 802			PROTOCOL_ERR("14.12.3.3");
 803			rc = -EIO;
 804			goto error;
 805		}
 806
 807		ddev->curr_nfc_dep_pni =
 808			DIGITAL_NFC_DEP_PFB_PNI(ddev->curr_nfc_dep_pni + 1);
 809
 810		kfree_skb(ddev->saved_skb);
 811		ddev->saved_skb = NULL;
 812
 813		resp = digital_recv_dep_data_gather(ddev, pfb, resp,
 814						    digital_in_send_ack,
 815						    data_exch);
 816		if (IS_ERR(resp)) {
 817			rc = PTR_ERR(resp);
 818			resp = NULL;
 819			goto error;
 820		}
 821
 822		/* If resp is NULL then we're still chaining so return and
 823		 * wait for the next part of the PDU.  Else, the PDU is
 824		 * complete so pass it up.
 825		 */
 826		if (!resp)
 827			return;
 828
 829		rc = 0;
 830		break;
 831
 832	case DIGITAL_NFC_DEP_PFB_ACK_NACK_PDU:
 833		if (DIGITAL_NFC_DEP_NACK_BIT_SET(pfb)) {
 834			PROTOCOL_ERR("14.12.4.5");
 835			rc = -EIO;
 836			goto exit;
 837		}
 838
 839		if (DIGITAL_NFC_DEP_PFB_PNI(pfb) != ddev->curr_nfc_dep_pni) {
 840			PROTOCOL_ERR("14.12.3.3");
 841			rc = -EIO;
 842			goto exit;
 843		}
 844
 845		ddev->curr_nfc_dep_pni =
 846			DIGITAL_NFC_DEP_PFB_PNI(ddev->curr_nfc_dep_pni + 1);
 847
 848		if (!ddev->chaining_skb) {
 849			PROTOCOL_ERR("14.12.4.3");
 850			rc = -EIO;
 851			goto exit;
 852		}
 853
 854		/* The initiator has received a valid ACK. Free the last sent
 855		 * PDU and keep on sending chained skb.
 856		 */
 857		kfree_skb(ddev->saved_skb);
 858		ddev->saved_skb = NULL;
 859
 860		rc = digital_in_send_dep_req(ddev, NULL,
 861					     ddev->chaining_skb,
 862					     ddev->data_exch);
 863		if (rc)
 864			goto error;
 865
 866		goto free_resp;
 867
 868	case DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU:
 869		if (!DIGITAL_NFC_DEP_PFB_IS_TIMEOUT(pfb)) { /* ATN */
 870			rc = digital_in_send_saved_skb(ddev, data_exch);
 871			if (rc)
 872				goto error;
 873
 874			goto free_resp;
 875		}
 876
 877		if (ddev->atn_count || ddev->nack_count) {
 878			PROTOCOL_ERR("14.12.4.4");
 879			rc = -EIO;
 880			goto error;
 881		}
 882
 883		rtox = DIGITAL_NFC_DEP_RTOX_VALUE(resp->data[0]);
 884		if (!rtox || rtox > DIGITAL_NFC_DEP_RTOX_MAX) {
 885			PROTOCOL_ERR("14.8.4.1");
 886			rc = -EIO;
 887			goto error;
 888		}
 889
 890		rc = digital_in_send_rtox(ddev, data_exch, rtox);
 891		if (rc)
 892			goto error;
 893
 894		goto free_resp;
 895	}
 896
 897exit:
 898	data_exch->cb(data_exch->cb_context, resp, rc);
 899
 900error:
 901	kfree(data_exch);
 902
 903	kfree_skb(ddev->chaining_skb);
 904	ddev->chaining_skb = NULL;
 905
 906	kfree_skb(ddev->saved_skb);
 907	ddev->saved_skb = NULL;
 908
 909	if (rc)
 910		kfree_skb(resp);
 911
 912	return;
 913
 914free_resp:
 915	dev_kfree_skb(resp);
 916}
 917
 918int digital_in_send_dep_req(struct nfc_digital_dev *ddev,
 919			    struct nfc_target *target, struct sk_buff *skb,
 920			    struct digital_data_exch *data_exch)
 921{
 922	struct digital_dep_req_res *dep_req;
 923	struct sk_buff *chaining_skb, *tmp_skb;
 924	int rc;
 925
 926	skb_push(skb, sizeof(struct digital_dep_req_res));
 927
 928	dep_req = (struct digital_dep_req_res *)skb->data;
 929
 930	dep_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT;
 931	dep_req->cmd = DIGITAL_CMD_DEP_REQ;
 932	dep_req->pfb = ddev->curr_nfc_dep_pni;
 933
 934	ddev->atn_count = 0;
 935	ddev->nack_count = 0;
 936
 937	chaining_skb = ddev->chaining_skb;
 938
 939	tmp_skb = digital_send_dep_data_prep(ddev, skb, dep_req, data_exch);
 940	if (IS_ERR(tmp_skb))
 941		return PTR_ERR(tmp_skb);
 942
 943	digital_skb_push_dep_sod(ddev, tmp_skb);
 944
 945	ddev->skb_add_crc(tmp_skb);
 946
 947	ddev->saved_skb = pskb_copy(tmp_skb, GFP_KERNEL);
 948
 949	rc = digital_in_send_cmd(ddev, tmp_skb, ddev->dep_rwt,
 950				 digital_in_recv_dep_res, data_exch);
 951	if (rc) {
 952		if (tmp_skb != skb)
 953			kfree_skb(tmp_skb);
 954
 955		kfree_skb(chaining_skb);
 956		ddev->chaining_skb = NULL;
 957
 958		kfree_skb(ddev->saved_skb);
 959		ddev->saved_skb = NULL;
 960	}
 961
 962	return rc;
 963}
 964
 965static void digital_tg_set_rf_tech(struct nfc_digital_dev *ddev, u8 rf_tech)
 966{
 967	ddev->curr_rf_tech = rf_tech;
 968
 969	ddev->skb_add_crc = digital_skb_add_crc_none;
 970	ddev->skb_check_crc = digital_skb_check_crc_none;
 971
 972	if (DIGITAL_DRV_CAPS_TG_CRC(ddev))
 973		return;
 974
 975	switch (ddev->curr_rf_tech) {
 976	case NFC_DIGITAL_RF_TECH_106A:
 977		ddev->skb_add_crc = digital_skb_add_crc_a;
 978		ddev->skb_check_crc = digital_skb_check_crc_a;
 979		break;
 980
 981	case NFC_DIGITAL_RF_TECH_212F:
 982	case NFC_DIGITAL_RF_TECH_424F:
 983		ddev->skb_add_crc = digital_skb_add_crc_f;
 984		ddev->skb_check_crc = digital_skb_check_crc_f;
 985		break;
 986
 987	default:
 988		break;
 989	}
 990}
 991
 992static int digital_tg_send_ack(struct nfc_digital_dev *ddev,
 993			       struct digital_data_exch *data_exch)
 994{
 995	struct digital_dep_req_res *dep_res;
 996	struct sk_buff *skb;
 997	int rc;
 998
 999	skb = digital_skb_alloc(ddev, 1);
1000	if (!skb)
1001		return -ENOMEM;
1002
1003	skb_push(skb, sizeof(struct digital_dep_req_res));
1004
1005	dep_res = (struct digital_dep_req_res *)skb->data;
1006
1007	dep_res->dir = DIGITAL_NFC_DEP_FRAME_DIR_IN;
1008	dep_res->cmd = DIGITAL_CMD_DEP_RES;
1009	dep_res->pfb = DIGITAL_NFC_DEP_PFB_ACK_NACK_PDU |
1010		       ddev->curr_nfc_dep_pni;
1011
1012	if (ddev->did) {
1013		dep_res->pfb |= DIGITAL_NFC_DEP_PFB_DID_BIT;
1014
1015		memcpy(skb_put(skb, sizeof(ddev->did)), &ddev->did,
1016		       sizeof(ddev->did));
1017	}
1018
1019	ddev->curr_nfc_dep_pni =
1020		DIGITAL_NFC_DEP_PFB_PNI(ddev->curr_nfc_dep_pni + 1);
1021
1022	digital_skb_push_dep_sod(ddev, skb);
1023
1024	ddev->skb_add_crc(skb);
1025
1026	ddev->saved_skb = pskb_copy(skb, GFP_KERNEL);
1027
1028	rc = digital_tg_send_cmd(ddev, skb, 1500, digital_tg_recv_dep_req,
1029				 data_exch);
1030	if (rc) {
1031		kfree_skb(skb);
1032		kfree_skb(ddev->saved_skb);
1033		ddev->saved_skb = NULL;
1034	}
1035
1036	return rc;
1037}
1038
1039static int digital_tg_send_atn(struct nfc_digital_dev *ddev)
1040{
1041	struct digital_dep_req_res *dep_res;
1042	struct sk_buff *skb;
1043	int rc;
1044
1045	skb = digital_skb_alloc(ddev, 1);
1046	if (!skb)
1047		return -ENOMEM;
1048
1049	skb_push(skb, sizeof(struct digital_dep_req_res));
1050
1051	dep_res = (struct digital_dep_req_res *)skb->data;
1052
1053	dep_res->dir = DIGITAL_NFC_DEP_FRAME_DIR_IN;
1054	dep_res->cmd = DIGITAL_CMD_DEP_RES;
1055	dep_res->pfb = DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU;
1056
1057	if (ddev->did) {
1058		dep_res->pfb |= DIGITAL_NFC_DEP_PFB_DID_BIT;
1059
1060		memcpy(skb_put(skb, sizeof(ddev->did)), &ddev->did,
1061		       sizeof(ddev->did));
1062	}
1063
1064	digital_skb_push_dep_sod(ddev, skb);
1065
1066	ddev->skb_add_crc(skb);
1067
1068	rc = digital_tg_send_cmd(ddev, skb, 1500, digital_tg_recv_dep_req,
1069				 NULL);
1070	if (rc)
1071		kfree_skb(skb);
1072
1073	return rc;
1074}
1075
1076static int digital_tg_send_saved_skb(struct nfc_digital_dev *ddev)
1077{
1078	int rc;
1079
1080	if (!ddev->saved_skb)
1081		return -EINVAL;
1082
1083	skb_get(ddev->saved_skb);
1084
1085	rc = digital_tg_send_cmd(ddev, ddev->saved_skb, 1500,
1086				 digital_tg_recv_dep_req, NULL);
1087	if (rc)
1088		kfree_skb(ddev->saved_skb);
1089
1090	return rc;
1091}
1092
1093static void digital_tg_recv_dep_req(struct nfc_digital_dev *ddev, void *arg,
1094				    struct sk_buff *resp)
1095{
1096	int rc;
1097	struct digital_dep_req_res *dep_req;
1098	u8 pfb;
1099	size_t size;
1100
1101	if (IS_ERR(resp)) {
1102		rc = PTR_ERR(resp);
1103		resp = NULL;
1104		goto exit;
1105	}
1106
1107	rc = ddev->skb_check_crc(resp);
1108	if (rc) {
1109		PROTOCOL_ERR("14.4.1.6");
1110		goto exit;
1111	}
1112
1113	rc = digital_skb_pull_dep_sod(ddev, resp);
1114	if (rc) {
1115		PROTOCOL_ERR("14.4.1.2");
1116		goto exit;
1117	}
1118
1119	if (resp->len > ddev->local_payload_max) {
1120		rc = -EMSGSIZE;
1121		goto exit;
1122	}
1123
1124	size = sizeof(struct digital_dep_req_res);
1125	dep_req = (struct digital_dep_req_res *)resp->data;
1126
1127	if (resp->len < size || dep_req->dir != DIGITAL_NFC_DEP_FRAME_DIR_OUT ||
1128	    dep_req->cmd != DIGITAL_CMD_DEP_REQ) {
1129		rc = -EIO;
1130		goto exit;
1131	}
1132
1133	pfb = dep_req->pfb;
1134
1135	if (DIGITAL_NFC_DEP_DID_BIT_SET(pfb)) {
1136		if (ddev->did && (ddev->did == resp->data[3])) {
1137			size++;
1138		} else {
1139			rc = -EIO;
1140			goto exit;
1141		}
1142	} else if (ddev->did) {
1143		rc = -EIO;
1144		goto exit;
1145	}
1146
1147	if (DIGITAL_NFC_DEP_NAD_BIT_SET(pfb)) {
1148		rc = -EIO;
1149		goto exit;
1150	}
1151
1152	if (size > resp->len) {
1153		rc = -EIO;
1154		goto exit;
1155	}
1156
1157	skb_pull(resp, size);
1158
1159	switch (DIGITAL_NFC_DEP_PFB_TYPE(pfb)) {
1160	case DIGITAL_NFC_DEP_PFB_I_PDU:
1161		pr_debug("DIGITAL_NFC_DEP_PFB_I_PDU\n");
1162
1163		if (ddev->atn_count) {
1164			/* The target has received (and replied to) at least one
1165			 * ATN DEP_REQ.
1166			 */
1167			ddev->atn_count = 0;
1168
1169			/* pni of resp PDU equal to the target current pni - 1
1170			 * means resp is the previous DEP_REQ PDU received from
1171			 * the initiator so the target replies with saved_skb
1172			 * which is the previous DEP_RES saved in
1173			 * digital_tg_send_dep_res().
1174			 */
1175			if (DIGITAL_NFC_DEP_PFB_PNI(pfb) ==
1176			  DIGITAL_NFC_DEP_PFB_PNI(ddev->curr_nfc_dep_pni - 1)) {
1177				rc = digital_tg_send_saved_skb(ddev);
1178				if (rc)
1179					goto exit;
1180
1181				goto free_resp;
1182			}
1183
1184			/* atn_count > 0 and PDU pni != curr_nfc_dep_pni - 1
1185			 * means the target probably did not received the last
1186			 * DEP_REQ PDU sent by the initiator. The target
1187			 * fallbacks to normal processing then.
1188			 */
1189		}
1190
1191		if (DIGITAL_NFC_DEP_PFB_PNI(pfb) != ddev->curr_nfc_dep_pni) {
1192			PROTOCOL_ERR("14.12.3.4");
1193			rc = -EIO;
1194			goto exit;
1195		}
1196
1197		kfree_skb(ddev->saved_skb);
1198		ddev->saved_skb = NULL;
1199
1200		resp = digital_recv_dep_data_gather(ddev, pfb, resp,
1201						    digital_tg_send_ack, NULL);
1202		if (IS_ERR(resp)) {
1203			rc = PTR_ERR(resp);
1204			resp = NULL;
1205			goto exit;
1206		}
1207
1208		/* If resp is NULL then we're still chaining so return and
1209		 * wait for the next part of the PDU.  Else, the PDU is
1210		 * complete so pass it up.
1211		 */
1212		if (!resp)
1213			return;
1214
1215		rc = 0;
1216		break;
1217	case DIGITAL_NFC_DEP_PFB_ACK_NACK_PDU:
1218		if (DIGITAL_NFC_DEP_NACK_BIT_SET(pfb)) { /* NACK */
1219			if (DIGITAL_NFC_DEP_PFB_PNI(pfb + 1) !=
1220						ddev->curr_nfc_dep_pni) {
1221				rc = -EIO;
1222				goto exit;
1223			}
1224
1225			ddev->atn_count = 0;
1226
1227			rc = digital_tg_send_saved_skb(ddev);
1228			if (rc)
1229				goto exit;
1230
1231			goto free_resp;
1232		}
1233
1234		/* ACK */
1235		if (ddev->atn_count) {
1236			/* The target has previously recevied one or more ATN
1237			 * PDUs.
1238			 */
1239			ddev->atn_count = 0;
1240
1241			/* If the ACK PNI is equal to the target PNI - 1 means
1242			 * that the initiator did not receive the previous PDU
1243			 * sent by the target so re-send it.
1244			 */
1245			if (DIGITAL_NFC_DEP_PFB_PNI(pfb + 1) ==
1246						ddev->curr_nfc_dep_pni) {
1247				rc = digital_tg_send_saved_skb(ddev);
1248				if (rc)
1249					goto exit;
1250
1251				goto free_resp;
1252			}
1253
1254			/* Otherwise, the target did not receive the previous
1255			 * ACK PDU from the initiator. Fallback to normal
1256			 * processing of chained PDU then.
1257			 */
1258		}
1259
1260		/* Keep on sending chained PDU */
1261		if (!ddev->chaining_skb ||
1262		    DIGITAL_NFC_DEP_PFB_PNI(pfb) !=
1263					ddev->curr_nfc_dep_pni) {
1264			rc = -EIO;
1265			goto exit;
1266		}
1267
1268		kfree_skb(ddev->saved_skb);
1269		ddev->saved_skb = NULL;
1270
1271		rc = digital_tg_send_dep_res(ddev, ddev->chaining_skb);
1272		if (rc)
1273			goto exit;
1274
1275		goto free_resp;
1276	case DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU:
1277		if (DIGITAL_NFC_DEP_PFB_IS_TIMEOUT(pfb)) {
1278			rc = -EINVAL;
1279			goto exit;
1280		}
1281
1282		rc = digital_tg_send_atn(ddev);
1283		if (rc)
1284			goto exit;
1285
1286		ddev->atn_count++;
1287
1288		goto free_resp;
1289	}
1290
1291	rc = nfc_tm_data_received(ddev->nfc_dev, resp);
 
 
1292
1293exit:
1294	kfree_skb(ddev->chaining_skb);
1295	ddev->chaining_skb = NULL;
1296
1297	ddev->atn_count = 0;
1298
1299	kfree_skb(ddev->saved_skb);
1300	ddev->saved_skb = NULL;
1301
1302	if (rc)
1303		kfree_skb(resp);
1304
1305	return;
1306
1307free_resp:
1308	dev_kfree_skb(resp);
1309}
1310
1311int digital_tg_send_dep_res(struct nfc_digital_dev *ddev, struct sk_buff *skb)
1312{
1313	struct digital_dep_req_res *dep_res;
1314	struct sk_buff *chaining_skb, *tmp_skb;
1315	int rc;
1316
1317	skb_push(skb, sizeof(struct digital_dep_req_res));
1318
1319	dep_res = (struct digital_dep_req_res *)skb->data;
1320
1321	dep_res->dir = DIGITAL_NFC_DEP_FRAME_DIR_IN;
1322	dep_res->cmd = DIGITAL_CMD_DEP_RES;
1323	dep_res->pfb = ddev->curr_nfc_dep_pni;
1324
1325	if (ddev->did) {
1326		dep_res->pfb |= DIGITAL_NFC_DEP_PFB_DID_BIT;
1327
1328		memcpy(skb_put(skb, sizeof(ddev->did)), &ddev->did,
1329		       sizeof(ddev->did));
1330	}
1331
1332	ddev->curr_nfc_dep_pni =
1333		DIGITAL_NFC_DEP_PFB_PNI(ddev->curr_nfc_dep_pni + 1);
1334
1335	chaining_skb = ddev->chaining_skb;
1336
1337	tmp_skb = digital_send_dep_data_prep(ddev, skb, dep_res, NULL);
1338	if (IS_ERR(tmp_skb))
1339		return PTR_ERR(tmp_skb);
1340
1341	digital_skb_push_dep_sod(ddev, tmp_skb);
1342
1343	ddev->skb_add_crc(tmp_skb);
1344
1345	ddev->saved_skb = pskb_copy(tmp_skb, GFP_KERNEL);
1346
1347	rc = digital_tg_send_cmd(ddev, tmp_skb, 1500, digital_tg_recv_dep_req,
1348				 NULL);
1349	if (rc) {
1350		if (tmp_skb != skb)
1351			kfree_skb(tmp_skb);
1352
1353		kfree_skb(chaining_skb);
1354		ddev->chaining_skb = NULL;
1355
1356		kfree_skb(ddev->saved_skb);
1357		ddev->saved_skb = NULL;
1358	}
1359
1360	return rc;
1361}
1362
1363static void digital_tg_send_psl_res_complete(struct nfc_digital_dev *ddev,
1364					     void *arg, struct sk_buff *resp)
1365{
1366	u8 rf_tech = (unsigned long)arg;
1367
1368	if (IS_ERR(resp))
1369		return;
1370
1371	digital_tg_set_rf_tech(ddev, rf_tech);
1372
1373	digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH, rf_tech);
1374
1375	digital_tg_listen(ddev, 1500, digital_tg_recv_dep_req, NULL);
1376
1377	dev_kfree_skb(resp);
1378}
1379
1380static int digital_tg_send_psl_res(struct nfc_digital_dev *ddev, u8 did,
1381				   u8 rf_tech)
1382{
1383	struct digital_psl_res *psl_res;
1384	struct sk_buff *skb;
1385	int rc;
1386
1387	skb = digital_skb_alloc(ddev, sizeof(struct digital_psl_res));
1388	if (!skb)
1389		return -ENOMEM;
1390
1391	skb_put(skb, sizeof(struct digital_psl_res));
1392
1393	psl_res = (struct digital_psl_res *)skb->data;
1394
1395	psl_res->dir = DIGITAL_NFC_DEP_FRAME_DIR_IN;
1396	psl_res->cmd = DIGITAL_CMD_PSL_RES;
1397	psl_res->did = did;
1398
1399	digital_skb_push_dep_sod(ddev, skb);
1400
1401	ddev->skb_add_crc(skb);
1402
1403	ddev->curr_nfc_dep_pni = 0;
1404
1405	rc = digital_tg_send_cmd(ddev, skb, 0, digital_tg_send_psl_res_complete,
1406				 (void *)(unsigned long)rf_tech);
1407	if (rc)
1408		kfree_skb(skb);
1409
1410	return rc;
1411}
1412
1413static void digital_tg_recv_psl_req(struct nfc_digital_dev *ddev, void *arg,
1414				    struct sk_buff *resp)
1415{
1416	int rc;
1417	struct digital_psl_req *psl_req;
1418	u8 rf_tech;
1419	u8 dsi, payload_size, payload_bits;
1420
1421	if (IS_ERR(resp)) {
1422		rc = PTR_ERR(resp);
1423		resp = NULL;
1424		goto exit;
1425	}
1426
1427	rc = ddev->skb_check_crc(resp);
1428	if (rc) {
1429		PROTOCOL_ERR("14.4.1.6");
1430		goto exit;
1431	}
1432
1433	rc = digital_skb_pull_dep_sod(ddev, resp);
1434	if (rc) {
1435		PROTOCOL_ERR("14.4.1.2");
1436		goto exit;
1437	}
1438
1439	psl_req = (struct digital_psl_req *)resp->data;
1440
1441	if (resp->len != sizeof(struct digital_psl_req) ||
1442	    psl_req->dir != DIGITAL_NFC_DEP_FRAME_DIR_OUT ||
1443	    psl_req->cmd != DIGITAL_CMD_PSL_REQ) {
1444		rc = -EIO;
1445		goto exit;
1446	}
1447
1448	dsi = (psl_req->brs >> 3) & 0x07;
1449	switch (dsi) {
1450	case 0:
1451		rf_tech = NFC_DIGITAL_RF_TECH_106A;
1452		break;
1453	case 1:
1454		rf_tech = NFC_DIGITAL_RF_TECH_212F;
1455		break;
1456	case 2:
1457		rf_tech = NFC_DIGITAL_RF_TECH_424F;
1458		break;
1459	default:
1460		pr_err("Unsupported dsi value %d\n", dsi);
1461		goto exit;
1462	}
1463
1464	payload_bits = DIGITAL_PAYLOAD_FSL_TO_BITS(psl_req->fsl);
1465	payload_size = digital_payload_bits_to_size(payload_bits);
1466
1467	if (!payload_size || (payload_size > min(ddev->local_payload_max,
1468						 ddev->remote_payload_max))) {
1469		rc = -EINVAL;
1470		goto exit;
1471	}
1472
1473	ddev->local_payload_max = payload_size;
1474	ddev->remote_payload_max = payload_size;
1475
1476	rc = digital_tg_send_psl_res(ddev, psl_req->did, rf_tech);
1477
1478exit:
1479	kfree_skb(resp);
1480}
1481
1482static void digital_tg_send_atr_res_complete(struct nfc_digital_dev *ddev,
1483					     void *arg, struct sk_buff *resp)
1484{
1485	int offset;
1486
1487	if (IS_ERR(resp)) {
1488		digital_poll_next_tech(ddev);
1489		return;
1490	}
1491
1492	offset = 2;
1493	if (resp->data[0] == DIGITAL_NFC_DEP_NFCA_SOD_SB)
1494		offset++;
1495
1496	ddev->atn_count = 0;
1497
1498	if (resp->data[offset] == DIGITAL_CMD_PSL_REQ)
1499		digital_tg_recv_psl_req(ddev, arg, resp);
1500	else
1501		digital_tg_recv_dep_req(ddev, arg, resp);
1502}
1503
1504static int digital_tg_send_atr_res(struct nfc_digital_dev *ddev,
1505				   struct digital_atr_req *atr_req)
1506{
1507	struct digital_atr_res *atr_res;
1508	struct sk_buff *skb;
1509	u8 *gb, payload_bits;
1510	size_t gb_len;
1511	int rc;
1512
1513	gb = nfc_get_local_general_bytes(ddev->nfc_dev, &gb_len);
1514	if (!gb)
1515		gb_len = 0;
1516
1517	skb = digital_skb_alloc(ddev, sizeof(struct digital_atr_res) + gb_len);
1518	if (!skb)
1519		return -ENOMEM;
1520
1521	skb_put(skb, sizeof(struct digital_atr_res));
1522	atr_res = (struct digital_atr_res *)skb->data;
1523
1524	memset(atr_res, 0, sizeof(struct digital_atr_res));
1525
1526	atr_res->dir = DIGITAL_NFC_DEP_FRAME_DIR_IN;
1527	atr_res->cmd = DIGITAL_CMD_ATR_RES;
1528	memcpy(atr_res->nfcid3, atr_req->nfcid3, sizeof(atr_req->nfcid3));
1529	atr_res->to = DIGITAL_NFC_DEP_TG_MAX_WT;
1530
1531	ddev->local_payload_max = DIGITAL_PAYLOAD_SIZE_MAX;
1532	payload_bits = digital_payload_size_to_bits(ddev->local_payload_max);
1533	atr_res->pp = DIGITAL_PAYLOAD_BITS_TO_PP(payload_bits);
1534
1535	if (gb_len) {
1536		skb_put(skb, gb_len);
1537
1538		atr_res->pp |= DIGITAL_GB_BIT;
1539		memcpy(atr_res->gb, gb, gb_len);
1540	}
1541
1542	digital_skb_push_dep_sod(ddev, skb);
1543
1544	ddev->skb_add_crc(skb);
1545
1546	ddev->curr_nfc_dep_pni = 0;
1547
1548	rc = digital_tg_send_cmd(ddev, skb, 999,
1549				 digital_tg_send_atr_res_complete, NULL);
1550	if (rc)
1551		kfree_skb(skb);
1552
1553	return rc;
1554}
1555
1556void digital_tg_recv_atr_req(struct nfc_digital_dev *ddev, void *arg,
1557			     struct sk_buff *resp)
1558{
1559	int rc;
1560	struct digital_atr_req *atr_req;
1561	size_t gb_len, min_size;
1562	u8 poll_tech_count, payload_bits;
1563
1564	if (IS_ERR(resp)) {
1565		rc = PTR_ERR(resp);
1566		resp = NULL;
1567		goto exit;
1568	}
1569
1570	if (!resp->len) {
1571		rc = -EIO;
1572		goto exit;
1573	}
1574
1575	if (resp->data[0] == DIGITAL_NFC_DEP_NFCA_SOD_SB) {
1576		min_size = DIGITAL_ATR_REQ_MIN_SIZE + 2;
1577		digital_tg_set_rf_tech(ddev, NFC_DIGITAL_RF_TECH_106A);
1578	} else {
1579		min_size = DIGITAL_ATR_REQ_MIN_SIZE + 1;
1580		digital_tg_set_rf_tech(ddev, NFC_DIGITAL_RF_TECH_212F);
1581	}
1582
1583	if (resp->len < min_size) {
1584		rc = -EIO;
1585		goto exit;
1586	}
1587
1588	ddev->curr_protocol = NFC_PROTO_NFC_DEP_MASK;
1589
1590	rc = ddev->skb_check_crc(resp);
1591	if (rc) {
1592		PROTOCOL_ERR("14.4.1.6");
1593		goto exit;
1594	}
1595
1596	rc = digital_skb_pull_dep_sod(ddev, resp);
1597	if (rc) {
1598		PROTOCOL_ERR("14.4.1.2");
1599		goto exit;
1600	}
1601
1602	atr_req = (struct digital_atr_req *)resp->data;
1603
1604	if (atr_req->dir != DIGITAL_NFC_DEP_FRAME_DIR_OUT ||
1605	    atr_req->cmd != DIGITAL_CMD_ATR_REQ ||
1606	    atr_req->did > DIGITAL_DID_MAX) {
1607		rc = -EINVAL;
1608		goto exit;
1609	}
1610
1611	payload_bits = DIGITAL_PAYLOAD_PP_TO_BITS(atr_req->pp);
1612	ddev->remote_payload_max = digital_payload_bits_to_size(payload_bits);
1613
1614	if (!ddev->remote_payload_max) {
1615		rc = -EINVAL;
1616		goto exit;
1617	}
1618
1619	ddev->did = atr_req->did;
1620
1621	rc = digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
1622				     NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED);
1623	if (rc)
1624		goto exit;
1625
1626	rc = digital_tg_send_atr_res(ddev, atr_req);
1627	if (rc)
1628		goto exit;
1629
1630	gb_len = resp->len - sizeof(struct digital_atr_req);
1631
1632	poll_tech_count = ddev->poll_tech_count;
1633	ddev->poll_tech_count = 0;
1634
1635	rc = nfc_tm_activated(ddev->nfc_dev, NFC_PROTO_NFC_DEP_MASK,
1636			      NFC_COMM_PASSIVE, atr_req->gb, gb_len);
1637	if (rc) {
1638		ddev->poll_tech_count = poll_tech_count;
1639		goto exit;
1640	}
1641
1642	rc = 0;
1643exit:
1644	if (rc)
1645		digital_poll_next_tech(ddev);
1646
1647	dev_kfree_skb(resp);
1648}
v6.13.7
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * NFC Digital Protocol stack
   4 * Copyright (c) 2013, Intel Corporation.
 
 
 
 
 
 
 
 
 
 
   5 */
   6
   7#define pr_fmt(fmt) "digital: %s: " fmt, __func__
   8
   9#include "digital.h"
  10
  11#define DIGITAL_NFC_DEP_N_RETRY_NACK	2
  12#define DIGITAL_NFC_DEP_N_RETRY_ATN	2
  13
  14#define DIGITAL_NFC_DEP_FRAME_DIR_OUT 0xD4
  15#define DIGITAL_NFC_DEP_FRAME_DIR_IN  0xD5
  16
  17#define DIGITAL_NFC_DEP_NFCA_SOD_SB   0xF0
  18
  19#define DIGITAL_CMD_ATR_REQ 0x00
  20#define DIGITAL_CMD_ATR_RES 0x01
  21#define DIGITAL_CMD_PSL_REQ 0x04
  22#define DIGITAL_CMD_PSL_RES 0x05
  23#define DIGITAL_CMD_DEP_REQ 0x06
  24#define DIGITAL_CMD_DEP_RES 0x07
  25
  26#define DIGITAL_ATR_REQ_MIN_SIZE 16
  27#define DIGITAL_ATR_REQ_MAX_SIZE 64
  28
  29#define DIGITAL_ATR_RES_TO_WT(s)	((s) & 0xF)
  30
  31#define DIGITAL_DID_MAX	14
  32
  33#define DIGITAL_PAYLOAD_SIZE_MAX	254
  34#define DIGITAL_PAYLOAD_BITS_TO_PP(s)	(((s) & 0x3) << 4)
  35#define DIGITAL_PAYLOAD_PP_TO_BITS(s)	(((s) >> 4) & 0x3)
  36#define DIGITAL_PAYLOAD_BITS_TO_FSL(s)	((s) & 0x3)
  37#define DIGITAL_PAYLOAD_FSL_TO_BITS(s)	((s) & 0x3)
  38
  39#define DIGITAL_GB_BIT	0x02
  40
 
 
 
  41#define DIGITAL_NFC_DEP_PFB_TYPE(pfb) ((pfb) & 0xE0)
  42
  43#define DIGITAL_NFC_DEP_PFB_TIMEOUT_BIT 0x10
  44#define DIGITAL_NFC_DEP_PFB_MI_BIT	0x10
  45#define DIGITAL_NFC_DEP_PFB_NACK_BIT	0x10
  46#define DIGITAL_NFC_DEP_PFB_DID_BIT	0x04
  47
  48#define DIGITAL_NFC_DEP_PFB_IS_TIMEOUT(pfb) \
  49				((pfb) & DIGITAL_NFC_DEP_PFB_TIMEOUT_BIT)
  50#define DIGITAL_NFC_DEP_MI_BIT_SET(pfb)  ((pfb) & DIGITAL_NFC_DEP_PFB_MI_BIT)
  51#define DIGITAL_NFC_DEP_NACK_BIT_SET(pfb) ((pfb) & DIGITAL_NFC_DEP_PFB_NACK_BIT)
  52#define DIGITAL_NFC_DEP_NAD_BIT_SET(pfb) ((pfb) & 0x08)
  53#define DIGITAL_NFC_DEP_DID_BIT_SET(pfb) ((pfb) & DIGITAL_NFC_DEP_PFB_DID_BIT)
  54#define DIGITAL_NFC_DEP_PFB_PNI(pfb)     ((pfb) & 0x03)
  55
  56#define DIGITAL_NFC_DEP_RTOX_VALUE(data) ((data) & 0x3F)
  57#define DIGITAL_NFC_DEP_RTOX_MAX	 59
  58
  59#define DIGITAL_NFC_DEP_PFB_I_PDU          0x00
  60#define DIGITAL_NFC_DEP_PFB_ACK_NACK_PDU   0x40
  61#define DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU 0x80
  62
  63struct digital_atr_req {
  64	u8 dir;
  65	u8 cmd;
  66	u8 nfcid3[10];
  67	u8 did;
  68	u8 bs;
  69	u8 br;
  70	u8 pp;
  71	u8 gb[];
  72} __packed;
  73
  74struct digital_atr_res {
  75	u8 dir;
  76	u8 cmd;
  77	u8 nfcid3[10];
  78	u8 did;
  79	u8 bs;
  80	u8 br;
  81	u8 to;
  82	u8 pp;
  83	u8 gb[];
  84} __packed;
  85
  86struct digital_psl_req {
  87	u8 dir;
  88	u8 cmd;
  89	u8 did;
  90	u8 brs;
  91	u8 fsl;
  92} __packed;
  93
  94struct digital_psl_res {
  95	u8 dir;
  96	u8 cmd;
  97	u8 did;
  98} __packed;
  99
 100struct digital_dep_req_res {
 101	u8 dir;
 102	u8 cmd;
 103	u8 pfb;
 104} __packed;
 105
 106static void digital_in_recv_dep_res(struct nfc_digital_dev *ddev, void *arg,
 107				    struct sk_buff *resp);
 108static void digital_tg_recv_dep_req(struct nfc_digital_dev *ddev, void *arg,
 109				    struct sk_buff *resp);
 110
 111static const u8 digital_payload_bits_map[4] = {
 112	[0] = 64,
 113	[1] = 128,
 114	[2] = 192,
 115	[3] = 254
 116};
 117
 118/* Response Waiting Time for ATR_RES PDU in ms
 119 *
 120 * RWT(ATR_RES) = RWT(nfcdep,activation) + dRWT(nfcdep) + dT(nfcdep,initiator)
 121 *
 122 * with:
 123 *  RWT(nfcdep,activation) = 4096 * 2^12 / f(c) s
 124 *  dRWT(nfcdep) = 16 / f(c) s
 125 *  dT(nfcdep,initiator) = 100 ms
 126 *  f(c) = 13560000 Hz
 127 */
 128#define DIGITAL_ATR_RES_RWT 1337
 129
 130/* Response Waiting Time for other DEP PDUs in ms
 131 *
 132 * max_rwt = rwt + dRWT(nfcdep) + dT(nfcdep,initiator)
 133 *
 134 * with:
 135 *  rwt = (256 * 16 / f(c)) * 2^wt s
 136 *  dRWT(nfcdep) = 16 / f(c) s
 137 *  dT(nfcdep,initiator) = 100 ms
 138 *  f(c) = 13560000 Hz
 139 *  0 <= wt <= 14 (given by the target by the TO field of ATR_RES response)
 140 */
 141#define DIGITAL_NFC_DEP_IN_MAX_WT 14
 142#define DIGITAL_NFC_DEP_TG_MAX_WT 14
 143static const u16 digital_rwt_map[DIGITAL_NFC_DEP_IN_MAX_WT + 1] = {
 144	100,  101,  101,  102,  105,
 145	110,  119,  139,  177,  255,
 146	409,  719, 1337, 2575, 5049,
 147};
 148
 149static u8 digital_payload_bits_to_size(u8 payload_bits)
 150{
 151	if (payload_bits >= ARRAY_SIZE(digital_payload_bits_map))
 152		return 0;
 153
 154	return digital_payload_bits_map[payload_bits];
 155}
 156
 157static u8 digital_payload_size_to_bits(u8 payload_size)
 158{
 159	int i;
 160
 161	for (i = 0; i < ARRAY_SIZE(digital_payload_bits_map); i++)
 162		if (digital_payload_bits_map[i] == payload_size)
 163			return i;
 164
 165	return 0xff;
 166}
 167
 168static void digital_skb_push_dep_sod(struct nfc_digital_dev *ddev,
 169				     struct sk_buff *skb)
 170{
 171	skb_push(skb, sizeof(u8));
 172
 173	skb->data[0] = skb->len;
 174
 175	if (ddev->curr_rf_tech == NFC_DIGITAL_RF_TECH_106A)
 176		*(u8 *)skb_push(skb, sizeof(u8)) = DIGITAL_NFC_DEP_NFCA_SOD_SB;
 177}
 178
 179static int digital_skb_pull_dep_sod(struct nfc_digital_dev *ddev,
 180				    struct sk_buff *skb)
 181{
 182	u8 size;
 183
 184	if (skb->len < 2)
 185		return -EIO;
 186
 187	if (ddev->curr_rf_tech == NFC_DIGITAL_RF_TECH_106A)
 188		skb_pull(skb, sizeof(u8));
 189
 190	size = skb->data[0];
 191	if (size != skb->len)
 192		return -EIO;
 193
 194	skb_pull(skb, sizeof(u8));
 195
 196	return 0;
 197}
 198
 199static struct sk_buff *
 200digital_send_dep_data_prep(struct nfc_digital_dev *ddev, struct sk_buff *skb,
 201			   struct digital_dep_req_res *dep_req_res,
 202			   struct digital_data_exch *data_exch)
 203{
 204	struct sk_buff *new_skb;
 205
 206	if (skb->len > ddev->remote_payload_max) {
 207		dep_req_res->pfb |= DIGITAL_NFC_DEP_PFB_MI_BIT;
 208
 209		new_skb = digital_skb_alloc(ddev, ddev->remote_payload_max);
 210		if (!new_skb) {
 211			kfree_skb(ddev->chaining_skb);
 212			ddev->chaining_skb = NULL;
 213
 214			return ERR_PTR(-ENOMEM);
 215		}
 216
 217		skb_put_data(new_skb, skb->data, ddev->remote_payload_max);
 
 218		skb_pull(skb, ddev->remote_payload_max);
 219
 220		ddev->chaining_skb = skb;
 221		ddev->data_exch = data_exch;
 222	} else {
 223		ddev->chaining_skb = NULL;
 224		new_skb = skb;
 225	}
 226
 227	return new_skb;
 228}
 229
 230static struct sk_buff *
 231digital_recv_dep_data_gather(struct nfc_digital_dev *ddev, u8 pfb,
 232			     struct sk_buff *resp,
 233			     int (*send_ack)(struct nfc_digital_dev *ddev,
 234					     struct digital_data_exch
 235							     *data_exch),
 236			     struct digital_data_exch *data_exch)
 237{
 238	struct sk_buff *new_skb;
 239	int rc;
 240
 241	if (DIGITAL_NFC_DEP_MI_BIT_SET(pfb) && (!ddev->chaining_skb)) {
 242		ddev->chaining_skb =
 243			nfc_alloc_recv_skb(8 * ddev->local_payload_max,
 244					   GFP_KERNEL);
 245		if (!ddev->chaining_skb) {
 246			rc = -ENOMEM;
 247			goto error;
 248		}
 249	}
 250
 251	if (ddev->chaining_skb) {
 252		if (resp->len > skb_tailroom(ddev->chaining_skb)) {
 253			new_skb = skb_copy_expand(ddev->chaining_skb,
 254						  skb_headroom(
 255							  ddev->chaining_skb),
 256						  8 * ddev->local_payload_max,
 257						  GFP_KERNEL);
 258			if (!new_skb) {
 259				rc = -ENOMEM;
 260				goto error;
 261			}
 262
 263			kfree_skb(ddev->chaining_skb);
 264			ddev->chaining_skb = new_skb;
 265		}
 266
 267		skb_put_data(ddev->chaining_skb, resp->data, resp->len);
 
 268
 269		kfree_skb(resp);
 270		resp = NULL;
 271
 272		if (DIGITAL_NFC_DEP_MI_BIT_SET(pfb)) {
 273			rc = send_ack(ddev, data_exch);
 274			if (rc)
 275				goto error;
 276
 277			return NULL;
 278		}
 279
 280		resp = ddev->chaining_skb;
 281		ddev->chaining_skb = NULL;
 282	}
 283
 284	return resp;
 285
 286error:
 287	kfree_skb(resp);
 288
 289	kfree_skb(ddev->chaining_skb);
 290	ddev->chaining_skb = NULL;
 291
 292	return ERR_PTR(rc);
 293}
 294
 295static void digital_in_recv_psl_res(struct nfc_digital_dev *ddev, void *arg,
 296				    struct sk_buff *resp)
 297{
 298	struct nfc_target *target = arg;
 299	struct digital_psl_res *psl_res;
 300	int rc;
 301
 302	if (IS_ERR(resp)) {
 303		rc = PTR_ERR(resp);
 304		resp = NULL;
 305		goto exit;
 306	}
 307
 308	rc = ddev->skb_check_crc(resp);
 309	if (rc) {
 310		PROTOCOL_ERR("14.4.1.6");
 311		goto exit;
 312	}
 313
 314	rc = digital_skb_pull_dep_sod(ddev, resp);
 315	if (rc) {
 316		PROTOCOL_ERR("14.4.1.2");
 317		goto exit;
 318	}
 319
 320	psl_res = (struct digital_psl_res *)resp->data;
 321
 322	if ((resp->len != sizeof(*psl_res)) ||
 323	    (psl_res->dir != DIGITAL_NFC_DEP_FRAME_DIR_IN) ||
 324	    (psl_res->cmd != DIGITAL_CMD_PSL_RES)) {
 325		rc = -EIO;
 326		goto exit;
 327	}
 328
 329	rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH,
 330				     NFC_DIGITAL_RF_TECH_424F);
 331	if (rc)
 332		goto exit;
 333
 334	rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
 335				     NFC_DIGITAL_FRAMING_NFCF_NFC_DEP);
 336	if (rc)
 337		goto exit;
 338
 339	if (!DIGITAL_DRV_CAPS_IN_CRC(ddev) &&
 340	    (ddev->curr_rf_tech == NFC_DIGITAL_RF_TECH_106A)) {
 341		ddev->skb_add_crc = digital_skb_add_crc_f;
 342		ddev->skb_check_crc = digital_skb_check_crc_f;
 343	}
 344
 345	ddev->curr_rf_tech = NFC_DIGITAL_RF_TECH_424F;
 346
 347	nfc_dep_link_is_up(ddev->nfc_dev, target->idx, NFC_COMM_ACTIVE,
 348			   NFC_RF_INITIATOR);
 349
 350	ddev->curr_nfc_dep_pni = 0;
 351
 352exit:
 353	dev_kfree_skb(resp);
 354
 355	if (rc)
 356		ddev->curr_protocol = 0;
 357}
 358
 359static int digital_in_send_psl_req(struct nfc_digital_dev *ddev,
 360				   struct nfc_target *target)
 361{
 362	struct sk_buff *skb;
 363	struct digital_psl_req *psl_req;
 364	int rc;
 365	u8 payload_size, payload_bits;
 366
 367	skb = digital_skb_alloc(ddev, sizeof(*psl_req));
 368	if (!skb)
 369		return -ENOMEM;
 370
 371	skb_put(skb, sizeof(*psl_req));
 372
 373	psl_req = (struct digital_psl_req *)skb->data;
 374
 375	psl_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT;
 376	psl_req->cmd = DIGITAL_CMD_PSL_REQ;
 377	psl_req->did = 0;
 378	psl_req->brs = (0x2 << 3) | 0x2; /* 424F both directions */
 379
 380	payload_size = min(ddev->local_payload_max, ddev->remote_payload_max);
 381	payload_bits = digital_payload_size_to_bits(payload_size);
 382	psl_req->fsl = DIGITAL_PAYLOAD_BITS_TO_FSL(payload_bits);
 383
 384	ddev->local_payload_max = payload_size;
 385	ddev->remote_payload_max = payload_size;
 386
 387	digital_skb_push_dep_sod(ddev, skb);
 388
 389	ddev->skb_add_crc(skb);
 390
 391	rc = digital_in_send_cmd(ddev, skb, ddev->dep_rwt,
 392				 digital_in_recv_psl_res, target);
 393	if (rc)
 394		kfree_skb(skb);
 395
 396	return rc;
 397}
 398
 399static void digital_in_recv_atr_res(struct nfc_digital_dev *ddev, void *arg,
 400				 struct sk_buff *resp)
 401{
 402	struct nfc_target *target = arg;
 403	struct digital_atr_res *atr_res;
 404	u8 gb_len, payload_bits;
 405	u8 wt;
 406	int rc;
 407
 408	if (IS_ERR(resp)) {
 409		rc = PTR_ERR(resp);
 410		resp = NULL;
 411		goto exit;
 412	}
 413
 414	rc = ddev->skb_check_crc(resp);
 415	if (rc) {
 416		PROTOCOL_ERR("14.4.1.6");
 417		goto exit;
 418	}
 419
 420	rc = digital_skb_pull_dep_sod(ddev, resp);
 421	if (rc) {
 422		PROTOCOL_ERR("14.4.1.2");
 423		goto exit;
 424	}
 425
 426	if (resp->len < sizeof(struct digital_atr_res)) {
 427		rc = -EIO;
 428		goto exit;
 429	}
 430
 431	gb_len = resp->len - sizeof(struct digital_atr_res);
 432
 433	atr_res = (struct digital_atr_res *)resp->data;
 434
 435	wt = DIGITAL_ATR_RES_TO_WT(atr_res->to);
 436	if (wt > DIGITAL_NFC_DEP_IN_MAX_WT)
 437		wt = DIGITAL_NFC_DEP_IN_MAX_WT;
 438	ddev->dep_rwt = digital_rwt_map[wt];
 439
 440	payload_bits = DIGITAL_PAYLOAD_PP_TO_BITS(atr_res->pp);
 441	ddev->remote_payload_max = digital_payload_bits_to_size(payload_bits);
 442
 443	if (!ddev->remote_payload_max) {
 444		rc = -EINVAL;
 445		goto exit;
 446	}
 447
 448	rc = nfc_set_remote_general_bytes(ddev->nfc_dev, atr_res->gb, gb_len);
 449	if (rc)
 450		goto exit;
 451
 452	if ((ddev->protocols & NFC_PROTO_FELICA_MASK) &&
 453	    (ddev->curr_rf_tech != NFC_DIGITAL_RF_TECH_424F)) {
 454		rc = digital_in_send_psl_req(ddev, target);
 455		if (!rc)
 456			goto exit;
 457	}
 458
 459	rc = nfc_dep_link_is_up(ddev->nfc_dev, target->idx, NFC_COMM_ACTIVE,
 460				NFC_RF_INITIATOR);
 461
 462	ddev->curr_nfc_dep_pni = 0;
 463
 464exit:
 465	dev_kfree_skb(resp);
 466
 467	if (rc)
 468		ddev->curr_protocol = 0;
 469}
 470
 471int digital_in_send_atr_req(struct nfc_digital_dev *ddev,
 472			    struct nfc_target *target, __u8 comm_mode, __u8 *gb,
 473			    size_t gb_len)
 474{
 475	struct sk_buff *skb;
 476	struct digital_atr_req *atr_req;
 477	uint size;
 478	int rc;
 479	u8 payload_bits;
 480
 481	size = DIGITAL_ATR_REQ_MIN_SIZE + gb_len;
 482
 483	if (size > DIGITAL_ATR_REQ_MAX_SIZE) {
 484		PROTOCOL_ERR("14.6.1.1");
 485		return -EINVAL;
 486	}
 487
 488	skb = digital_skb_alloc(ddev, size);
 489	if (!skb)
 490		return -ENOMEM;
 491
 492	skb_put(skb, sizeof(struct digital_atr_req));
 493
 494	atr_req = (struct digital_atr_req *)skb->data;
 495	memset(atr_req, 0, sizeof(struct digital_atr_req));
 496
 497	atr_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT;
 498	atr_req->cmd = DIGITAL_CMD_ATR_REQ;
 499	if (target->nfcid2_len)
 500		memcpy(atr_req->nfcid3, target->nfcid2, NFC_NFCID2_MAXSIZE);
 501	else
 502		get_random_bytes(atr_req->nfcid3, NFC_NFCID3_MAXSIZE);
 503
 504	atr_req->did = 0;
 505	atr_req->bs = 0;
 506	atr_req->br = 0;
 507
 508	ddev->local_payload_max = DIGITAL_PAYLOAD_SIZE_MAX;
 509	payload_bits = digital_payload_size_to_bits(ddev->local_payload_max);
 510	atr_req->pp = DIGITAL_PAYLOAD_BITS_TO_PP(payload_bits);
 511
 512	if (gb_len) {
 513		atr_req->pp |= DIGITAL_GB_BIT;
 514		skb_put_data(skb, gb, gb_len);
 515	}
 516
 517	digital_skb_push_dep_sod(ddev, skb);
 518
 519	ddev->skb_add_crc(skb);
 520
 521	rc = digital_in_send_cmd(ddev, skb, DIGITAL_ATR_RES_RWT,
 522				 digital_in_recv_atr_res, target);
 523	if (rc)
 524		kfree_skb(skb);
 525
 526	return rc;
 527}
 528
 529static int digital_in_send_ack(struct nfc_digital_dev *ddev,
 530			       struct digital_data_exch *data_exch)
 531{
 532	struct digital_dep_req_res *dep_req;
 533	struct sk_buff *skb;
 534	int rc;
 535
 536	skb = digital_skb_alloc(ddev, 1);
 537	if (!skb)
 538		return -ENOMEM;
 539
 540	skb_push(skb, sizeof(struct digital_dep_req_res));
 541
 542	dep_req = (struct digital_dep_req_res *)skb->data;
 543
 544	dep_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT;
 545	dep_req->cmd = DIGITAL_CMD_DEP_REQ;
 546	dep_req->pfb = DIGITAL_NFC_DEP_PFB_ACK_NACK_PDU |
 547		       ddev->curr_nfc_dep_pni;
 548
 549	digital_skb_push_dep_sod(ddev, skb);
 550
 551	ddev->skb_add_crc(skb);
 552
 553	ddev->saved_skb = pskb_copy(skb, GFP_KERNEL);
 554
 555	rc = digital_in_send_cmd(ddev, skb, ddev->dep_rwt,
 556				 digital_in_recv_dep_res, data_exch);
 557	if (rc) {
 558		kfree_skb(skb);
 559		kfree_skb(ddev->saved_skb);
 560		ddev->saved_skb = NULL;
 561	}
 562
 563	return rc;
 564}
 565
 566static int digital_in_send_nack(struct nfc_digital_dev *ddev,
 567				struct digital_data_exch *data_exch)
 568{
 569	struct digital_dep_req_res *dep_req;
 570	struct sk_buff *skb;
 571	int rc;
 572
 573	skb = digital_skb_alloc(ddev, 1);
 574	if (!skb)
 575		return -ENOMEM;
 576
 577	skb_push(skb, sizeof(struct digital_dep_req_res));
 578
 579	dep_req = (struct digital_dep_req_res *)skb->data;
 580
 581	dep_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT;
 582	dep_req->cmd = DIGITAL_CMD_DEP_REQ;
 583	dep_req->pfb = DIGITAL_NFC_DEP_PFB_ACK_NACK_PDU |
 584		       DIGITAL_NFC_DEP_PFB_NACK_BIT | ddev->curr_nfc_dep_pni;
 585
 586	digital_skb_push_dep_sod(ddev, skb);
 587
 588	ddev->skb_add_crc(skb);
 589
 590	rc = digital_in_send_cmd(ddev, skb, ddev->dep_rwt,
 591				 digital_in_recv_dep_res, data_exch);
 592	if (rc)
 593		kfree_skb(skb);
 594
 595	return rc;
 596}
 597
 598static int digital_in_send_atn(struct nfc_digital_dev *ddev,
 599			       struct digital_data_exch *data_exch)
 600{
 601	struct digital_dep_req_res *dep_req;
 602	struct sk_buff *skb;
 603	int rc;
 604
 605	skb = digital_skb_alloc(ddev, 1);
 606	if (!skb)
 607		return -ENOMEM;
 608
 609	skb_push(skb, sizeof(struct digital_dep_req_res));
 610
 611	dep_req = (struct digital_dep_req_res *)skb->data;
 612
 613	dep_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT;
 614	dep_req->cmd = DIGITAL_CMD_DEP_REQ;
 615	dep_req->pfb = DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU;
 616
 617	digital_skb_push_dep_sod(ddev, skb);
 618
 619	ddev->skb_add_crc(skb);
 620
 621	rc = digital_in_send_cmd(ddev, skb, ddev->dep_rwt,
 622				 digital_in_recv_dep_res, data_exch);
 623	if (rc)
 624		kfree_skb(skb);
 625
 626	return rc;
 627}
 628
 629static int digital_in_send_rtox(struct nfc_digital_dev *ddev,
 630				struct digital_data_exch *data_exch, u8 rtox)
 631{
 632	struct digital_dep_req_res *dep_req;
 633	struct sk_buff *skb;
 634	int rc;
 635	u16 rwt_int;
 636
 637	rwt_int = ddev->dep_rwt * rtox;
 638	if (rwt_int > digital_rwt_map[DIGITAL_NFC_DEP_IN_MAX_WT])
 639		rwt_int = digital_rwt_map[DIGITAL_NFC_DEP_IN_MAX_WT];
 640
 641	skb = digital_skb_alloc(ddev, 1);
 642	if (!skb)
 643		return -ENOMEM;
 644
 645	skb_put_u8(skb, rtox);
 646
 647	skb_push(skb, sizeof(struct digital_dep_req_res));
 648
 649	dep_req = (struct digital_dep_req_res *)skb->data;
 650
 651	dep_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT;
 652	dep_req->cmd = DIGITAL_CMD_DEP_REQ;
 653	dep_req->pfb = DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU |
 654		       DIGITAL_NFC_DEP_PFB_TIMEOUT_BIT;
 655
 656	digital_skb_push_dep_sod(ddev, skb);
 657
 658	ddev->skb_add_crc(skb);
 659
 660	rc = digital_in_send_cmd(ddev, skb, rwt_int,
 661				 digital_in_recv_dep_res, data_exch);
 662	if (rc)
 663		kfree_skb(skb);
 664
 665	return rc;
 666}
 667
 668static int digital_in_send_saved_skb(struct nfc_digital_dev *ddev,
 669				     struct digital_data_exch *data_exch)
 670{
 671	int rc;
 672
 673	if (!ddev->saved_skb)
 674		return -EINVAL;
 675
 676	skb_get(ddev->saved_skb);
 677
 678	rc = digital_in_send_cmd(ddev, ddev->saved_skb, ddev->dep_rwt,
 679				 digital_in_recv_dep_res, data_exch);
 680	if (rc)
 681		kfree_skb(ddev->saved_skb);
 682
 683	return rc;
 684}
 685
 686static void digital_in_recv_dep_res(struct nfc_digital_dev *ddev, void *arg,
 687				    struct sk_buff *resp)
 688{
 689	struct digital_data_exch *data_exch = arg;
 690	struct digital_dep_req_res *dep_res;
 691	u8 pfb;
 692	uint size;
 693	int rc;
 694	u8 rtox;
 695
 696	if (IS_ERR(resp)) {
 697		rc = PTR_ERR(resp);
 698		resp = NULL;
 699
 700		if ((rc == -EIO || (rc == -ETIMEDOUT && ddev->nack_count)) &&
 701		    (ddev->nack_count++ < DIGITAL_NFC_DEP_N_RETRY_NACK)) {
 702			ddev->atn_count = 0;
 703
 704			rc = digital_in_send_nack(ddev, data_exch);
 705			if (rc)
 706				goto error;
 707
 708			return;
 709		} else if ((rc == -ETIMEDOUT) &&
 710			   (ddev->atn_count++ < DIGITAL_NFC_DEP_N_RETRY_ATN)) {
 711			ddev->nack_count = 0;
 712
 713			rc = digital_in_send_atn(ddev, data_exch);
 714			if (rc)
 715				goto error;
 716
 717			return;
 718		}
 719
 720		goto exit;
 721	}
 722
 723	rc = digital_skb_pull_dep_sod(ddev, resp);
 724	if (rc) {
 725		PROTOCOL_ERR("14.4.1.2");
 726		goto exit;
 727	}
 728
 729	rc = ddev->skb_check_crc(resp);
 730	if (rc) {
 731		if ((resp->len >= 4) &&
 732		    (ddev->nack_count++ < DIGITAL_NFC_DEP_N_RETRY_NACK)) {
 733			ddev->atn_count = 0;
 734
 735			rc = digital_in_send_nack(ddev, data_exch);
 736			if (rc)
 737				goto error;
 738
 739			kfree_skb(resp);
 740
 741			return;
 742		}
 743
 744		PROTOCOL_ERR("14.4.1.6");
 745		goto error;
 746	}
 747
 748	ddev->atn_count = 0;
 749	ddev->nack_count = 0;
 750
 751	if (resp->len > ddev->local_payload_max) {
 752		rc = -EMSGSIZE;
 753		goto exit;
 754	}
 755
 756	size = sizeof(struct digital_dep_req_res);
 757	dep_res = (struct digital_dep_req_res *)resp->data;
 758
 759	if (resp->len < size || dep_res->dir != DIGITAL_NFC_DEP_FRAME_DIR_IN ||
 760	    dep_res->cmd != DIGITAL_CMD_DEP_RES) {
 761		rc = -EIO;
 762		goto error;
 763	}
 764
 765	pfb = dep_res->pfb;
 766
 767	if (DIGITAL_NFC_DEP_DID_BIT_SET(pfb)) {
 768		PROTOCOL_ERR("14.8.2.1");
 769		rc = -EIO;
 770		goto error;
 771	}
 772
 773	if (DIGITAL_NFC_DEP_NAD_BIT_SET(pfb)) {
 774		rc = -EIO;
 775		goto exit;
 776	}
 777
 778	if (size > resp->len) {
 779		rc = -EIO;
 780		goto error;
 781	}
 782
 783	skb_pull(resp, size);
 784
 785	switch (DIGITAL_NFC_DEP_PFB_TYPE(pfb)) {
 786	case DIGITAL_NFC_DEP_PFB_I_PDU:
 787		if (DIGITAL_NFC_DEP_PFB_PNI(pfb) != ddev->curr_nfc_dep_pni) {
 788			PROTOCOL_ERR("14.12.3.3");
 789			rc = -EIO;
 790			goto error;
 791		}
 792
 793		ddev->curr_nfc_dep_pni =
 794			DIGITAL_NFC_DEP_PFB_PNI(ddev->curr_nfc_dep_pni + 1);
 795
 796		kfree_skb(ddev->saved_skb);
 797		ddev->saved_skb = NULL;
 798
 799		resp = digital_recv_dep_data_gather(ddev, pfb, resp,
 800						    digital_in_send_ack,
 801						    data_exch);
 802		if (IS_ERR(resp)) {
 803			rc = PTR_ERR(resp);
 804			resp = NULL;
 805			goto error;
 806		}
 807
 808		/* If resp is NULL then we're still chaining so return and
 809		 * wait for the next part of the PDU.  Else, the PDU is
 810		 * complete so pass it up.
 811		 */
 812		if (!resp)
 813			return;
 814
 815		rc = 0;
 816		break;
 817
 818	case DIGITAL_NFC_DEP_PFB_ACK_NACK_PDU:
 819		if (DIGITAL_NFC_DEP_NACK_BIT_SET(pfb)) {
 820			PROTOCOL_ERR("14.12.4.5");
 821			rc = -EIO;
 822			goto exit;
 823		}
 824
 825		if (DIGITAL_NFC_DEP_PFB_PNI(pfb) != ddev->curr_nfc_dep_pni) {
 826			PROTOCOL_ERR("14.12.3.3");
 827			rc = -EIO;
 828			goto exit;
 829		}
 830
 831		ddev->curr_nfc_dep_pni =
 832			DIGITAL_NFC_DEP_PFB_PNI(ddev->curr_nfc_dep_pni + 1);
 833
 834		if (!ddev->chaining_skb) {
 835			PROTOCOL_ERR("14.12.4.3");
 836			rc = -EIO;
 837			goto exit;
 838		}
 839
 840		/* The initiator has received a valid ACK. Free the last sent
 841		 * PDU and keep on sending chained skb.
 842		 */
 843		kfree_skb(ddev->saved_skb);
 844		ddev->saved_skb = NULL;
 845
 846		rc = digital_in_send_dep_req(ddev, NULL,
 847					     ddev->chaining_skb,
 848					     ddev->data_exch);
 849		if (rc)
 850			goto error;
 851
 852		goto free_resp;
 853
 854	case DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU:
 855		if (!DIGITAL_NFC_DEP_PFB_IS_TIMEOUT(pfb)) { /* ATN */
 856			rc = digital_in_send_saved_skb(ddev, data_exch);
 857			if (rc)
 858				goto error;
 859
 860			goto free_resp;
 861		}
 862
 863		if (ddev->atn_count || ddev->nack_count) {
 864			PROTOCOL_ERR("14.12.4.4");
 865			rc = -EIO;
 866			goto error;
 867		}
 868
 869		rtox = DIGITAL_NFC_DEP_RTOX_VALUE(resp->data[0]);
 870		if (!rtox || rtox > DIGITAL_NFC_DEP_RTOX_MAX) {
 871			PROTOCOL_ERR("14.8.4.1");
 872			rc = -EIO;
 873			goto error;
 874		}
 875
 876		rc = digital_in_send_rtox(ddev, data_exch, rtox);
 877		if (rc)
 878			goto error;
 879
 880		goto free_resp;
 881	}
 882
 883exit:
 884	data_exch->cb(data_exch->cb_context, resp, rc);
 885
 886error:
 887	kfree(data_exch);
 888
 889	kfree_skb(ddev->chaining_skb);
 890	ddev->chaining_skb = NULL;
 891
 892	kfree_skb(ddev->saved_skb);
 893	ddev->saved_skb = NULL;
 894
 895	if (rc)
 896		kfree_skb(resp);
 897
 898	return;
 899
 900free_resp:
 901	dev_kfree_skb(resp);
 902}
 903
 904int digital_in_send_dep_req(struct nfc_digital_dev *ddev,
 905			    struct nfc_target *target, struct sk_buff *skb,
 906			    struct digital_data_exch *data_exch)
 907{
 908	struct digital_dep_req_res *dep_req;
 909	struct sk_buff *chaining_skb, *tmp_skb;
 910	int rc;
 911
 912	skb_push(skb, sizeof(struct digital_dep_req_res));
 913
 914	dep_req = (struct digital_dep_req_res *)skb->data;
 915
 916	dep_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT;
 917	dep_req->cmd = DIGITAL_CMD_DEP_REQ;
 918	dep_req->pfb = ddev->curr_nfc_dep_pni;
 919
 920	ddev->atn_count = 0;
 921	ddev->nack_count = 0;
 922
 923	chaining_skb = ddev->chaining_skb;
 924
 925	tmp_skb = digital_send_dep_data_prep(ddev, skb, dep_req, data_exch);
 926	if (IS_ERR(tmp_skb))
 927		return PTR_ERR(tmp_skb);
 928
 929	digital_skb_push_dep_sod(ddev, tmp_skb);
 930
 931	ddev->skb_add_crc(tmp_skb);
 932
 933	ddev->saved_skb = pskb_copy(tmp_skb, GFP_KERNEL);
 934
 935	rc = digital_in_send_cmd(ddev, tmp_skb, ddev->dep_rwt,
 936				 digital_in_recv_dep_res, data_exch);
 937	if (rc) {
 938		if (tmp_skb != skb)
 939			kfree_skb(tmp_skb);
 940
 941		kfree_skb(chaining_skb);
 942		ddev->chaining_skb = NULL;
 943
 944		kfree_skb(ddev->saved_skb);
 945		ddev->saved_skb = NULL;
 946	}
 947
 948	return rc;
 949}
 950
 951static void digital_tg_set_rf_tech(struct nfc_digital_dev *ddev, u8 rf_tech)
 952{
 953	ddev->curr_rf_tech = rf_tech;
 954
 955	ddev->skb_add_crc = digital_skb_add_crc_none;
 956	ddev->skb_check_crc = digital_skb_check_crc_none;
 957
 958	if (DIGITAL_DRV_CAPS_TG_CRC(ddev))
 959		return;
 960
 961	switch (ddev->curr_rf_tech) {
 962	case NFC_DIGITAL_RF_TECH_106A:
 963		ddev->skb_add_crc = digital_skb_add_crc_a;
 964		ddev->skb_check_crc = digital_skb_check_crc_a;
 965		break;
 966
 967	case NFC_DIGITAL_RF_TECH_212F:
 968	case NFC_DIGITAL_RF_TECH_424F:
 969		ddev->skb_add_crc = digital_skb_add_crc_f;
 970		ddev->skb_check_crc = digital_skb_check_crc_f;
 971		break;
 972
 973	default:
 974		break;
 975	}
 976}
 977
 978static int digital_tg_send_ack(struct nfc_digital_dev *ddev,
 979			       struct digital_data_exch *data_exch)
 980{
 981	struct digital_dep_req_res *dep_res;
 982	struct sk_buff *skb;
 983	int rc;
 984
 985	skb = digital_skb_alloc(ddev, 1);
 986	if (!skb)
 987		return -ENOMEM;
 988
 989	skb_push(skb, sizeof(struct digital_dep_req_res));
 990
 991	dep_res = (struct digital_dep_req_res *)skb->data;
 992
 993	dep_res->dir = DIGITAL_NFC_DEP_FRAME_DIR_IN;
 994	dep_res->cmd = DIGITAL_CMD_DEP_RES;
 995	dep_res->pfb = DIGITAL_NFC_DEP_PFB_ACK_NACK_PDU |
 996		       ddev->curr_nfc_dep_pni;
 997
 998	if (ddev->did) {
 999		dep_res->pfb |= DIGITAL_NFC_DEP_PFB_DID_BIT;
1000
1001		skb_put_data(skb, &ddev->did, sizeof(ddev->did));
 
1002	}
1003
1004	ddev->curr_nfc_dep_pni =
1005		DIGITAL_NFC_DEP_PFB_PNI(ddev->curr_nfc_dep_pni + 1);
1006
1007	digital_skb_push_dep_sod(ddev, skb);
1008
1009	ddev->skb_add_crc(skb);
1010
1011	ddev->saved_skb = pskb_copy(skb, GFP_KERNEL);
1012
1013	rc = digital_tg_send_cmd(ddev, skb, 1500, digital_tg_recv_dep_req,
1014				 data_exch);
1015	if (rc) {
1016		kfree_skb(skb);
1017		kfree_skb(ddev->saved_skb);
1018		ddev->saved_skb = NULL;
1019	}
1020
1021	return rc;
1022}
1023
1024static int digital_tg_send_atn(struct nfc_digital_dev *ddev)
1025{
1026	struct digital_dep_req_res *dep_res;
1027	struct sk_buff *skb;
1028	int rc;
1029
1030	skb = digital_skb_alloc(ddev, 1);
1031	if (!skb)
1032		return -ENOMEM;
1033
1034	skb_push(skb, sizeof(struct digital_dep_req_res));
1035
1036	dep_res = (struct digital_dep_req_res *)skb->data;
1037
1038	dep_res->dir = DIGITAL_NFC_DEP_FRAME_DIR_IN;
1039	dep_res->cmd = DIGITAL_CMD_DEP_RES;
1040	dep_res->pfb = DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU;
1041
1042	if (ddev->did) {
1043		dep_res->pfb |= DIGITAL_NFC_DEP_PFB_DID_BIT;
1044
1045		skb_put_data(skb, &ddev->did, sizeof(ddev->did));
 
1046	}
1047
1048	digital_skb_push_dep_sod(ddev, skb);
1049
1050	ddev->skb_add_crc(skb);
1051
1052	rc = digital_tg_send_cmd(ddev, skb, 1500, digital_tg_recv_dep_req,
1053				 NULL);
1054	if (rc)
1055		kfree_skb(skb);
1056
1057	return rc;
1058}
1059
1060static int digital_tg_send_saved_skb(struct nfc_digital_dev *ddev)
1061{
1062	int rc;
1063
1064	if (!ddev->saved_skb)
1065		return -EINVAL;
1066
1067	skb_get(ddev->saved_skb);
1068
1069	rc = digital_tg_send_cmd(ddev, ddev->saved_skb, 1500,
1070				 digital_tg_recv_dep_req, NULL);
1071	if (rc)
1072		kfree_skb(ddev->saved_skb);
1073
1074	return rc;
1075}
1076
1077static void digital_tg_recv_dep_req(struct nfc_digital_dev *ddev, void *arg,
1078				    struct sk_buff *resp)
1079{
1080	int rc;
1081	struct digital_dep_req_res *dep_req;
1082	u8 pfb;
1083	size_t size;
1084
1085	if (IS_ERR(resp)) {
1086		rc = PTR_ERR(resp);
1087		resp = NULL;
1088		goto exit;
1089	}
1090
1091	rc = ddev->skb_check_crc(resp);
1092	if (rc) {
1093		PROTOCOL_ERR("14.4.1.6");
1094		goto exit;
1095	}
1096
1097	rc = digital_skb_pull_dep_sod(ddev, resp);
1098	if (rc) {
1099		PROTOCOL_ERR("14.4.1.2");
1100		goto exit;
1101	}
1102
1103	if (resp->len > ddev->local_payload_max) {
1104		rc = -EMSGSIZE;
1105		goto exit;
1106	}
1107
1108	size = sizeof(struct digital_dep_req_res);
1109	dep_req = (struct digital_dep_req_res *)resp->data;
1110
1111	if (resp->len < size || dep_req->dir != DIGITAL_NFC_DEP_FRAME_DIR_OUT ||
1112	    dep_req->cmd != DIGITAL_CMD_DEP_REQ) {
1113		rc = -EIO;
1114		goto exit;
1115	}
1116
1117	pfb = dep_req->pfb;
1118
1119	if (DIGITAL_NFC_DEP_DID_BIT_SET(pfb)) {
1120		if (ddev->did && (ddev->did == resp->data[3])) {
1121			size++;
1122		} else {
1123			rc = -EIO;
1124			goto exit;
1125		}
1126	} else if (ddev->did) {
1127		rc = -EIO;
1128		goto exit;
1129	}
1130
1131	if (DIGITAL_NFC_DEP_NAD_BIT_SET(pfb)) {
1132		rc = -EIO;
1133		goto exit;
1134	}
1135
1136	if (size > resp->len) {
1137		rc = -EIO;
1138		goto exit;
1139	}
1140
1141	skb_pull(resp, size);
1142
1143	switch (DIGITAL_NFC_DEP_PFB_TYPE(pfb)) {
1144	case DIGITAL_NFC_DEP_PFB_I_PDU:
1145		pr_debug("DIGITAL_NFC_DEP_PFB_I_PDU\n");
1146
1147		if (ddev->atn_count) {
1148			/* The target has received (and replied to) at least one
1149			 * ATN DEP_REQ.
1150			 */
1151			ddev->atn_count = 0;
1152
1153			/* pni of resp PDU equal to the target current pni - 1
1154			 * means resp is the previous DEP_REQ PDU received from
1155			 * the initiator so the target replies with saved_skb
1156			 * which is the previous DEP_RES saved in
1157			 * digital_tg_send_dep_res().
1158			 */
1159			if (DIGITAL_NFC_DEP_PFB_PNI(pfb) ==
1160			  DIGITAL_NFC_DEP_PFB_PNI(ddev->curr_nfc_dep_pni - 1)) {
1161				rc = digital_tg_send_saved_skb(ddev);
1162				if (rc)
1163					goto exit;
1164
1165				goto free_resp;
1166			}
1167
1168			/* atn_count > 0 and PDU pni != curr_nfc_dep_pni - 1
1169			 * means the target probably did not received the last
1170			 * DEP_REQ PDU sent by the initiator. The target
1171			 * fallbacks to normal processing then.
1172			 */
1173		}
1174
1175		if (DIGITAL_NFC_DEP_PFB_PNI(pfb) != ddev->curr_nfc_dep_pni) {
1176			PROTOCOL_ERR("14.12.3.4");
1177			rc = -EIO;
1178			goto exit;
1179		}
1180
1181		kfree_skb(ddev->saved_skb);
1182		ddev->saved_skb = NULL;
1183
1184		resp = digital_recv_dep_data_gather(ddev, pfb, resp,
1185						    digital_tg_send_ack, NULL);
1186		if (IS_ERR(resp)) {
1187			rc = PTR_ERR(resp);
1188			resp = NULL;
1189			goto exit;
1190		}
1191
1192		/* If resp is NULL then we're still chaining so return and
1193		 * wait for the next part of the PDU.  Else, the PDU is
1194		 * complete so pass it up.
1195		 */
1196		if (!resp)
1197			return;
1198
1199		rc = 0;
1200		break;
1201	case DIGITAL_NFC_DEP_PFB_ACK_NACK_PDU:
1202		if (DIGITAL_NFC_DEP_NACK_BIT_SET(pfb)) { /* NACK */
1203			if (DIGITAL_NFC_DEP_PFB_PNI(pfb + 1) !=
1204						ddev->curr_nfc_dep_pni) {
1205				rc = -EIO;
1206				goto exit;
1207			}
1208
1209			ddev->atn_count = 0;
1210
1211			rc = digital_tg_send_saved_skb(ddev);
1212			if (rc)
1213				goto exit;
1214
1215			goto free_resp;
1216		}
1217
1218		/* ACK */
1219		if (ddev->atn_count) {
1220			/* The target has previously received one or more ATN
1221			 * PDUs.
1222			 */
1223			ddev->atn_count = 0;
1224
1225			/* If the ACK PNI is equal to the target PNI - 1 means
1226			 * that the initiator did not receive the previous PDU
1227			 * sent by the target so re-send it.
1228			 */
1229			if (DIGITAL_NFC_DEP_PFB_PNI(pfb + 1) ==
1230						ddev->curr_nfc_dep_pni) {
1231				rc = digital_tg_send_saved_skb(ddev);
1232				if (rc)
1233					goto exit;
1234
1235				goto free_resp;
1236			}
1237
1238			/* Otherwise, the target did not receive the previous
1239			 * ACK PDU from the initiator. Fallback to normal
1240			 * processing of chained PDU then.
1241			 */
1242		}
1243
1244		/* Keep on sending chained PDU */
1245		if (!ddev->chaining_skb ||
1246		    DIGITAL_NFC_DEP_PFB_PNI(pfb) !=
1247					ddev->curr_nfc_dep_pni) {
1248			rc = -EIO;
1249			goto exit;
1250		}
1251
1252		kfree_skb(ddev->saved_skb);
1253		ddev->saved_skb = NULL;
1254
1255		rc = digital_tg_send_dep_res(ddev, ddev->chaining_skb);
1256		if (rc)
1257			goto exit;
1258
1259		goto free_resp;
1260	case DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU:
1261		if (DIGITAL_NFC_DEP_PFB_IS_TIMEOUT(pfb)) {
1262			rc = -EINVAL;
1263			goto exit;
1264		}
1265
1266		rc = digital_tg_send_atn(ddev);
1267		if (rc)
1268			goto exit;
1269
1270		ddev->atn_count++;
1271
1272		goto free_resp;
1273	}
1274
1275	rc = nfc_tm_data_received(ddev->nfc_dev, resp);
1276	if (rc)
1277		resp = NULL;
1278
1279exit:
1280	kfree_skb(ddev->chaining_skb);
1281	ddev->chaining_skb = NULL;
1282
1283	ddev->atn_count = 0;
1284
1285	kfree_skb(ddev->saved_skb);
1286	ddev->saved_skb = NULL;
1287
1288	if (rc)
1289		kfree_skb(resp);
1290
1291	return;
1292
1293free_resp:
1294	dev_kfree_skb(resp);
1295}
1296
1297int digital_tg_send_dep_res(struct nfc_digital_dev *ddev, struct sk_buff *skb)
1298{
1299	struct digital_dep_req_res *dep_res;
1300	struct sk_buff *chaining_skb, *tmp_skb;
1301	int rc;
1302
1303	skb_push(skb, sizeof(struct digital_dep_req_res));
1304
1305	dep_res = (struct digital_dep_req_res *)skb->data;
1306
1307	dep_res->dir = DIGITAL_NFC_DEP_FRAME_DIR_IN;
1308	dep_res->cmd = DIGITAL_CMD_DEP_RES;
1309	dep_res->pfb = ddev->curr_nfc_dep_pni;
1310
1311	if (ddev->did) {
1312		dep_res->pfb |= DIGITAL_NFC_DEP_PFB_DID_BIT;
1313
1314		skb_put_data(skb, &ddev->did, sizeof(ddev->did));
 
1315	}
1316
1317	ddev->curr_nfc_dep_pni =
1318		DIGITAL_NFC_DEP_PFB_PNI(ddev->curr_nfc_dep_pni + 1);
1319
1320	chaining_skb = ddev->chaining_skb;
1321
1322	tmp_skb = digital_send_dep_data_prep(ddev, skb, dep_res, NULL);
1323	if (IS_ERR(tmp_skb))
1324		return PTR_ERR(tmp_skb);
1325
1326	digital_skb_push_dep_sod(ddev, tmp_skb);
1327
1328	ddev->skb_add_crc(tmp_skb);
1329
1330	ddev->saved_skb = pskb_copy(tmp_skb, GFP_KERNEL);
1331
1332	rc = digital_tg_send_cmd(ddev, tmp_skb, 1500, digital_tg_recv_dep_req,
1333				 NULL);
1334	if (rc) {
1335		if (tmp_skb != skb)
1336			kfree_skb(tmp_skb);
1337
1338		kfree_skb(chaining_skb);
1339		ddev->chaining_skb = NULL;
1340
1341		kfree_skb(ddev->saved_skb);
1342		ddev->saved_skb = NULL;
1343	}
1344
1345	return rc;
1346}
1347
1348static void digital_tg_send_psl_res_complete(struct nfc_digital_dev *ddev,
1349					     void *arg, struct sk_buff *resp)
1350{
1351	u8 rf_tech = (unsigned long)arg;
1352
1353	if (IS_ERR(resp))
1354		return;
1355
1356	digital_tg_set_rf_tech(ddev, rf_tech);
1357
1358	digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH, rf_tech);
1359
1360	digital_tg_listen(ddev, 1500, digital_tg_recv_dep_req, NULL);
1361
1362	dev_kfree_skb(resp);
1363}
1364
1365static int digital_tg_send_psl_res(struct nfc_digital_dev *ddev, u8 did,
1366				   u8 rf_tech)
1367{
1368	struct digital_psl_res *psl_res;
1369	struct sk_buff *skb;
1370	int rc;
1371
1372	skb = digital_skb_alloc(ddev, sizeof(struct digital_psl_res));
1373	if (!skb)
1374		return -ENOMEM;
1375
1376	skb_put(skb, sizeof(struct digital_psl_res));
1377
1378	psl_res = (struct digital_psl_res *)skb->data;
1379
1380	psl_res->dir = DIGITAL_NFC_DEP_FRAME_DIR_IN;
1381	psl_res->cmd = DIGITAL_CMD_PSL_RES;
1382	psl_res->did = did;
1383
1384	digital_skb_push_dep_sod(ddev, skb);
1385
1386	ddev->skb_add_crc(skb);
1387
1388	ddev->curr_nfc_dep_pni = 0;
1389
1390	rc = digital_tg_send_cmd(ddev, skb, 0, digital_tg_send_psl_res_complete,
1391				 (void *)(unsigned long)rf_tech);
1392	if (rc)
1393		kfree_skb(skb);
1394
1395	return rc;
1396}
1397
1398static void digital_tg_recv_psl_req(struct nfc_digital_dev *ddev, void *arg,
1399				    struct sk_buff *resp)
1400{
1401	int rc;
1402	struct digital_psl_req *psl_req;
1403	u8 rf_tech;
1404	u8 dsi, payload_size, payload_bits;
1405
1406	if (IS_ERR(resp)) {
1407		rc = PTR_ERR(resp);
1408		resp = NULL;
1409		goto exit;
1410	}
1411
1412	rc = ddev->skb_check_crc(resp);
1413	if (rc) {
1414		PROTOCOL_ERR("14.4.1.6");
1415		goto exit;
1416	}
1417
1418	rc = digital_skb_pull_dep_sod(ddev, resp);
1419	if (rc) {
1420		PROTOCOL_ERR("14.4.1.2");
1421		goto exit;
1422	}
1423
1424	psl_req = (struct digital_psl_req *)resp->data;
1425
1426	if (resp->len != sizeof(struct digital_psl_req) ||
1427	    psl_req->dir != DIGITAL_NFC_DEP_FRAME_DIR_OUT ||
1428	    psl_req->cmd != DIGITAL_CMD_PSL_REQ) {
1429		rc = -EIO;
1430		goto exit;
1431	}
1432
1433	dsi = (psl_req->brs >> 3) & 0x07;
1434	switch (dsi) {
1435	case 0:
1436		rf_tech = NFC_DIGITAL_RF_TECH_106A;
1437		break;
1438	case 1:
1439		rf_tech = NFC_DIGITAL_RF_TECH_212F;
1440		break;
1441	case 2:
1442		rf_tech = NFC_DIGITAL_RF_TECH_424F;
1443		break;
1444	default:
1445		pr_err("Unsupported dsi value %d\n", dsi);
1446		goto exit;
1447	}
1448
1449	payload_bits = DIGITAL_PAYLOAD_FSL_TO_BITS(psl_req->fsl);
1450	payload_size = digital_payload_bits_to_size(payload_bits);
1451
1452	if (!payload_size || (payload_size > min(ddev->local_payload_max,
1453						 ddev->remote_payload_max))) {
1454		rc = -EINVAL;
1455		goto exit;
1456	}
1457
1458	ddev->local_payload_max = payload_size;
1459	ddev->remote_payload_max = payload_size;
1460
1461	rc = digital_tg_send_psl_res(ddev, psl_req->did, rf_tech);
1462
1463exit:
1464	kfree_skb(resp);
1465}
1466
1467static void digital_tg_send_atr_res_complete(struct nfc_digital_dev *ddev,
1468					     void *arg, struct sk_buff *resp)
1469{
1470	int offset;
1471
1472	if (IS_ERR(resp)) {
1473		digital_poll_next_tech(ddev);
1474		return;
1475	}
1476
1477	offset = 2;
1478	if (resp->data[0] == DIGITAL_NFC_DEP_NFCA_SOD_SB)
1479		offset++;
1480
1481	ddev->atn_count = 0;
1482
1483	if (resp->data[offset] == DIGITAL_CMD_PSL_REQ)
1484		digital_tg_recv_psl_req(ddev, arg, resp);
1485	else
1486		digital_tg_recv_dep_req(ddev, arg, resp);
1487}
1488
1489static int digital_tg_send_atr_res(struct nfc_digital_dev *ddev,
1490				   struct digital_atr_req *atr_req)
1491{
1492	struct digital_atr_res *atr_res;
1493	struct sk_buff *skb;
1494	u8 *gb, payload_bits;
1495	size_t gb_len;
1496	int rc;
1497
1498	gb = nfc_get_local_general_bytes(ddev->nfc_dev, &gb_len);
1499	if (!gb)
1500		gb_len = 0;
1501
1502	skb = digital_skb_alloc(ddev, sizeof(struct digital_atr_res) + gb_len);
1503	if (!skb)
1504		return -ENOMEM;
1505
1506	skb_put(skb, sizeof(struct digital_atr_res));
1507	atr_res = (struct digital_atr_res *)skb->data;
1508
1509	memset(atr_res, 0, sizeof(struct digital_atr_res));
1510
1511	atr_res->dir = DIGITAL_NFC_DEP_FRAME_DIR_IN;
1512	atr_res->cmd = DIGITAL_CMD_ATR_RES;
1513	memcpy(atr_res->nfcid3, atr_req->nfcid3, sizeof(atr_req->nfcid3));
1514	atr_res->to = DIGITAL_NFC_DEP_TG_MAX_WT;
1515
1516	ddev->local_payload_max = DIGITAL_PAYLOAD_SIZE_MAX;
1517	payload_bits = digital_payload_size_to_bits(ddev->local_payload_max);
1518	atr_res->pp = DIGITAL_PAYLOAD_BITS_TO_PP(payload_bits);
1519
1520	if (gb_len) {
1521		skb_put(skb, gb_len);
1522
1523		atr_res->pp |= DIGITAL_GB_BIT;
1524		memcpy(atr_res->gb, gb, gb_len);
1525	}
1526
1527	digital_skb_push_dep_sod(ddev, skb);
1528
1529	ddev->skb_add_crc(skb);
1530
1531	ddev->curr_nfc_dep_pni = 0;
1532
1533	rc = digital_tg_send_cmd(ddev, skb, 999,
1534				 digital_tg_send_atr_res_complete, NULL);
1535	if (rc)
1536		kfree_skb(skb);
1537
1538	return rc;
1539}
1540
1541void digital_tg_recv_atr_req(struct nfc_digital_dev *ddev, void *arg,
1542			     struct sk_buff *resp)
1543{
1544	int rc;
1545	struct digital_atr_req *atr_req;
1546	size_t gb_len, min_size;
1547	u8 poll_tech_count, payload_bits;
1548
1549	if (IS_ERR(resp)) {
1550		rc = PTR_ERR(resp);
1551		resp = NULL;
1552		goto exit;
1553	}
1554
1555	if (!resp->len) {
1556		rc = -EIO;
1557		goto exit;
1558	}
1559
1560	if (resp->data[0] == DIGITAL_NFC_DEP_NFCA_SOD_SB) {
1561		min_size = DIGITAL_ATR_REQ_MIN_SIZE + 2;
1562		digital_tg_set_rf_tech(ddev, NFC_DIGITAL_RF_TECH_106A);
1563	} else {
1564		min_size = DIGITAL_ATR_REQ_MIN_SIZE + 1;
1565		digital_tg_set_rf_tech(ddev, NFC_DIGITAL_RF_TECH_212F);
1566	}
1567
1568	if (resp->len < min_size) {
1569		rc = -EIO;
1570		goto exit;
1571	}
1572
1573	ddev->curr_protocol = NFC_PROTO_NFC_DEP_MASK;
1574
1575	rc = ddev->skb_check_crc(resp);
1576	if (rc) {
1577		PROTOCOL_ERR("14.4.1.6");
1578		goto exit;
1579	}
1580
1581	rc = digital_skb_pull_dep_sod(ddev, resp);
1582	if (rc) {
1583		PROTOCOL_ERR("14.4.1.2");
1584		goto exit;
1585	}
1586
1587	atr_req = (struct digital_atr_req *)resp->data;
1588
1589	if (atr_req->dir != DIGITAL_NFC_DEP_FRAME_DIR_OUT ||
1590	    atr_req->cmd != DIGITAL_CMD_ATR_REQ ||
1591	    atr_req->did > DIGITAL_DID_MAX) {
1592		rc = -EINVAL;
1593		goto exit;
1594	}
1595
1596	payload_bits = DIGITAL_PAYLOAD_PP_TO_BITS(atr_req->pp);
1597	ddev->remote_payload_max = digital_payload_bits_to_size(payload_bits);
1598
1599	if (!ddev->remote_payload_max) {
1600		rc = -EINVAL;
1601		goto exit;
1602	}
1603
1604	ddev->did = atr_req->did;
1605
1606	rc = digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
1607				     NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED);
1608	if (rc)
1609		goto exit;
1610
1611	rc = digital_tg_send_atr_res(ddev, atr_req);
1612	if (rc)
1613		goto exit;
1614
1615	gb_len = resp->len - sizeof(struct digital_atr_req);
1616
1617	poll_tech_count = ddev->poll_tech_count;
1618	ddev->poll_tech_count = 0;
1619
1620	rc = nfc_tm_activated(ddev->nfc_dev, NFC_PROTO_NFC_DEP_MASK,
1621			      NFC_COMM_PASSIVE, atr_req->gb, gb_len);
1622	if (rc) {
1623		ddev->poll_tech_count = poll_tech_count;
1624		goto exit;
1625	}
1626
1627	rc = 0;
1628exit:
1629	if (rc)
1630		digital_poll_next_tech(ddev);
1631
1632	dev_kfree_skb(resp);
1633}