xref: /linux/net/nfc/digital_technology.c (revision 46ce8be2ced389bccd84bcc04a12cf2f4d0c22d1)
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_CMD_SENS_REQ    0x26
12 #define DIGITAL_CMD_ALL_REQ     0x52
13 #define DIGITAL_CMD_SEL_REQ_CL1 0x93
14 #define DIGITAL_CMD_SEL_REQ_CL2 0x95
15 #define DIGITAL_CMD_SEL_REQ_CL3 0x97
16 
17 #define DIGITAL_SDD_REQ_SEL_PAR 0x20
18 
19 #define DIGITAL_SDD_RES_CT  0x88
20 #define DIGITAL_SDD_RES_LEN 5
21 #define DIGITAL_SEL_RES_LEN 1
22 
23 #define DIGITAL_SEL_RES_NFCID1_COMPLETE(sel_res) (!((sel_res) & 0x04))
24 #define DIGITAL_SEL_RES_IS_T2T(sel_res) (!((sel_res) & 0x60))
25 #define DIGITAL_SEL_RES_IS_T4T(sel_res) ((sel_res) & 0x20)
26 #define DIGITAL_SEL_RES_IS_NFC_DEP(sel_res) ((sel_res) & 0x40)
27 
28 #define DIGITAL_SENS_RES_IS_T1T(sens_res) (((sens_res) & 0x0C00) == 0x0C00)
29 #define DIGITAL_SENS_RES_IS_VALID(sens_res) \
30 	((!((sens_res) & 0x001F) && (((sens_res) & 0x0C00) == 0x0C00)) || \
31 	(((sens_res) & 0x001F) && ((sens_res) & 0x0C00) != 0x0C00))
32 
33 #define DIGITAL_MIFARE_READ_RES_LEN 16
34 #define DIGITAL_MIFARE_ACK_RES	0x0A
35 
36 #define DIGITAL_CMD_SENSB_REQ			0x05
37 #define DIGITAL_SENSB_ADVANCED			BIT(5)
38 #define DIGITAL_SENSB_EXTENDED			BIT(4)
39 #define DIGITAL_SENSB_ALLB_REQ			BIT(3)
40 #define DIGITAL_SENSB_N(n)			((n) & 0x7)
41 
42 #define DIGITAL_CMD_SENSB_RES			0x50
43 
44 #define DIGITAL_CMD_ATTRIB_REQ			0x1D
45 #define DIGITAL_ATTRIB_P1_TR0_DEFAULT		(0x0 << 6)
46 #define DIGITAL_ATTRIB_P1_TR1_DEFAULT		(0x0 << 4)
47 #define DIGITAL_ATTRIB_P1_SUPRESS_EOS		BIT(3)
48 #define DIGITAL_ATTRIB_P1_SUPRESS_SOS		BIT(2)
49 #define DIGITAL_ATTRIB_P2_LISTEN_POLL_1		(0x0 << 6)
50 #define DIGITAL_ATTRIB_P2_POLL_LISTEN_1		(0x0 << 4)
51 #define DIGITAL_ATTRIB_P2_MAX_FRAME_256		0x8
52 #define DIGITAL_ATTRIB_P4_DID(n)		((n) & 0xf)
53 
54 #define DIGITAL_CMD_SENSF_REQ	0x00
55 #define DIGITAL_CMD_SENSF_RES	0x01
56 
57 #define DIGITAL_SENSF_RES_MIN_LENGTH 17
58 #define DIGITAL_SENSF_RES_RD_AP_B1   0x00
59 #define DIGITAL_SENSF_RES_RD_AP_B2   0x8F
60 
61 #define DIGITAL_SENSF_REQ_RC_NONE 0
62 #define DIGITAL_SENSF_REQ_RC_SC   1
63 #define DIGITAL_SENSF_REQ_RC_AP   2
64 
65 #define DIGITAL_CMD_ISO15693_INVENTORY_REQ	0x01
66 
67 #define DIGITAL_ISO15693_REQ_FLAG_DATA_RATE	BIT(1)
68 #define DIGITAL_ISO15693_REQ_FLAG_INVENTORY	BIT(2)
69 #define DIGITAL_ISO15693_REQ_FLAG_NB_SLOTS	BIT(5)
70 #define DIGITAL_ISO15693_RES_FLAG_ERROR		BIT(0)
71 #define DIGITAL_ISO15693_RES_IS_VALID(flags) \
72 	(!((flags) & DIGITAL_ISO15693_RES_FLAG_ERROR))
73 
74 #define DIGITAL_ISO_DEP_I_PCB	 0x02
75 #define DIGITAL_ISO_DEP_PNI(pni) ((pni) & 0x01)
76 
77 #define DIGITAL_ISO_DEP_PCB_TYPE(pcb) ((pcb) & 0xC0)
78 
79 #define DIGITAL_ISO_DEP_I_BLOCK 0x00
80 
81 #define DIGITAL_ISO_DEP_BLOCK_HAS_DID(pcb) ((pcb) & 0x08)
82 
83 static const u8 digital_ats_fsc[] = {
84 	 16,  24,  32,  40,  48,  64,  96, 128,
85 };
86 
87 #define DIGITAL_ATS_FSCI(t0) ((t0) & 0x0F)
88 #define DIGITAL_SENSB_FSCI(pi2) (((pi2) & 0xF0) >> 4)
89 #define DIGITAL_ATS_MAX_FSC  256
90 
91 #define DIGITAL_RATS_BYTE1 0xE0
92 #define DIGITAL_RATS_PARAM 0x80
93 
94 struct digital_sdd_res {
95 	u8 nfcid1[4];
96 	u8 bcc;
97 } __packed;
98 
99 struct digital_sel_req {
100 	u8 sel_cmd;
101 	u8 b2;
102 	u8 nfcid1[4];
103 	u8 bcc;
104 } __packed;
105 
106 struct digital_sensb_req {
107 	u8 cmd;
108 	u8 afi;
109 	u8 param;
110 } __packed;
111 
112 struct digital_sensb_res {
113 	u8 cmd;
114 	u8 nfcid0[4];
115 	u8 app_data[4];
116 	u8 proto_info[3];
117 } __packed;
118 
119 struct digital_attrib_req {
120 	u8 cmd;
121 	u8 nfcid0[4];
122 	u8 param1;
123 	u8 param2;
124 	u8 param3;
125 	u8 param4;
126 } __packed;
127 
128 struct digital_attrib_res {
129 	u8 mbli_did;
130 } __packed;
131 
132 struct digital_sensf_req {
133 	u8 cmd;
134 	u8 sc1;
135 	u8 sc2;
136 	u8 rc;
137 	u8 tsn;
138 } __packed;
139 
140 struct digital_sensf_res {
141 	u8 cmd;
142 	u8 nfcid2[8];
143 	u8 pad0[2];
144 	u8 pad1[3];
145 	u8 mrti_check;
146 	u8 mrti_update;
147 	u8 pad2;
148 	u8 rd[2];
149 } __packed;
150 
151 struct digital_iso15693_inv_req {
152 	u8 flags;
153 	u8 cmd;
154 	u8 mask_len;
155 	u64 mask;
156 } __packed;
157 
158 struct digital_iso15693_inv_res {
159 	u8 flags;
160 	u8 dsfid;
161 	u64 uid;
162 } __packed;
163 
164 static int digital_in_send_sdd_req(struct nfc_digital_dev *ddev,
165 				   struct nfc_target *target);
166 
167 int digital_in_iso_dep_pull_sod(struct nfc_digital_dev *ddev,
168 				struct sk_buff *skb)
169 {
170 	u8 pcb;
171 	u8 block_type;
172 
173 	if (skb->len < 1)
174 		return -EIO;
175 
176 	pcb = *skb->data;
177 	block_type = DIGITAL_ISO_DEP_PCB_TYPE(pcb);
178 
179 	/* No support fo R-block nor S-block */
180 	if (block_type != DIGITAL_ISO_DEP_I_BLOCK) {
181 		pr_err("ISO_DEP R-block and S-block not supported\n");
182 		return -EIO;
183 	}
184 
185 	if (DIGITAL_ISO_DEP_BLOCK_HAS_DID(pcb)) {
186 		pr_err("DID field in ISO_DEP PCB not supported\n");
187 		return -EIO;
188 	}
189 
190 	skb_pull(skb, 1);
191 
192 	return 0;
193 }
194 
195 int digital_in_iso_dep_push_sod(struct nfc_digital_dev *ddev,
196 				struct sk_buff *skb)
197 {
198 	/*
199 	 * Chaining not supported so skb->len + 1 PCB byte + 2 CRC bytes must
200 	 * not be greater than remote FSC
201 	 */
202 	if (skb->len + 3 > ddev->target_fsc)
203 		return -EIO;
204 
205 	skb_push(skb, 1);
206 
207 	*skb->data = DIGITAL_ISO_DEP_I_PCB | ddev->curr_nfc_dep_pni;
208 
209 	ddev->curr_nfc_dep_pni =
210 		DIGITAL_ISO_DEP_PNI(ddev->curr_nfc_dep_pni + 1);
211 
212 	return 0;
213 }
214 
215 static void digital_in_recv_ats(struct nfc_digital_dev *ddev, void *arg,
216 				struct sk_buff *resp)
217 {
218 	struct nfc_target *target = arg;
219 	u8 fsdi;
220 	int rc;
221 
222 	if (IS_ERR(resp)) {
223 		rc = PTR_ERR(resp);
224 		resp = NULL;
225 		goto exit;
226 	}
227 
228 	if (resp->len < 2) {
229 		rc = -EIO;
230 		goto exit;
231 	}
232 
233 	fsdi = DIGITAL_ATS_FSCI(resp->data[1]);
234 	if (fsdi >= 8)
235 		ddev->target_fsc = DIGITAL_ATS_MAX_FSC;
236 	else
237 		ddev->target_fsc = digital_ats_fsc[fsdi];
238 
239 	ddev->curr_nfc_dep_pni = 0;
240 
241 	rc = digital_target_found(ddev, target, NFC_PROTO_ISO14443);
242 
243 exit:
244 	dev_kfree_skb(resp);
245 	kfree(target);
246 
247 	if (rc)
248 		digital_poll_next_tech(ddev);
249 }
250 
251 static int digital_in_send_rats(struct nfc_digital_dev *ddev,
252 				struct nfc_target *target)
253 {
254 	int rc;
255 	struct sk_buff *skb;
256 
257 	skb = digital_skb_alloc(ddev, 2);
258 	if (!skb)
259 		return -ENOMEM;
260 
261 	skb_put_u8(skb, DIGITAL_RATS_BYTE1);
262 	skb_put_u8(skb, DIGITAL_RATS_PARAM);
263 
264 	rc = digital_in_send_cmd(ddev, skb, 30, digital_in_recv_ats,
265 				 target);
266 	if (rc)
267 		kfree_skb(skb);
268 
269 	return rc;
270 }
271 
272 static void digital_in_recv_sel_res(struct nfc_digital_dev *ddev, void *arg,
273 				    struct sk_buff *resp)
274 {
275 	struct nfc_target *target = arg;
276 	int rc;
277 	u8 sel_res;
278 	u8 nfc_proto;
279 
280 	if (IS_ERR(resp)) {
281 		rc = PTR_ERR(resp);
282 		resp = NULL;
283 		goto exit;
284 	}
285 
286 	if (!DIGITAL_DRV_CAPS_IN_CRC(ddev)) {
287 		rc = digital_skb_check_crc_a(resp);
288 		if (rc) {
289 			PROTOCOL_ERR("4.4.1.3");
290 			goto exit;
291 		}
292 	}
293 
294 	if (resp->len != DIGITAL_SEL_RES_LEN) {
295 		rc = -EIO;
296 		goto exit;
297 	}
298 
299 	sel_res = resp->data[0];
300 
301 	if (!DIGITAL_SEL_RES_NFCID1_COMPLETE(sel_res)) {
302 		rc = digital_in_send_sdd_req(ddev, target);
303 		if (rc)
304 			goto exit;
305 
306 		goto exit_free_skb;
307 	}
308 
309 	target->sel_res = sel_res;
310 
311 	if (DIGITAL_SEL_RES_IS_T2T(sel_res)) {
312 		nfc_proto = NFC_PROTO_MIFARE;
313 	} else if (DIGITAL_SEL_RES_IS_NFC_DEP(sel_res)) {
314 		nfc_proto = NFC_PROTO_NFC_DEP;
315 	} else if (DIGITAL_SEL_RES_IS_T4T(sel_res)) {
316 		rc = digital_in_send_rats(ddev, target);
317 		if (rc)
318 			goto exit;
319 		/*
320 		 * Skip target_found and don't free it for now. This will be
321 		 * done when receiving the ATS
322 		 */
323 		goto exit_free_skb;
324 	} else {
325 		rc = -EOPNOTSUPP;
326 		goto exit;
327 	}
328 
329 	rc = digital_target_found(ddev, target, nfc_proto);
330 
331 exit:
332 	kfree(target);
333 
334 exit_free_skb:
335 	dev_kfree_skb(resp);
336 
337 	if (rc)
338 		digital_poll_next_tech(ddev);
339 }
340 
341 static int digital_in_send_sel_req(struct nfc_digital_dev *ddev,
342 				   struct nfc_target *target,
343 				   struct digital_sdd_res *sdd_res)
344 {
345 	struct sk_buff *skb;
346 	struct digital_sel_req *sel_req;
347 	u8 sel_cmd;
348 	int rc;
349 
350 	skb = digital_skb_alloc(ddev, sizeof(struct digital_sel_req));
351 	if (!skb)
352 		return -ENOMEM;
353 
354 	skb_put(skb, sizeof(struct digital_sel_req));
355 	sel_req = (struct digital_sel_req *)skb->data;
356 
357 	if (target->nfcid1_len <= 4)
358 		sel_cmd = DIGITAL_CMD_SEL_REQ_CL1;
359 	else if (target->nfcid1_len < 10)
360 		sel_cmd = DIGITAL_CMD_SEL_REQ_CL2;
361 	else
362 		sel_cmd = DIGITAL_CMD_SEL_REQ_CL3;
363 
364 	sel_req->sel_cmd = sel_cmd;
365 	sel_req->b2 = 0x70;
366 	memcpy(sel_req->nfcid1, sdd_res->nfcid1, 4);
367 	sel_req->bcc = sdd_res->bcc;
368 
369 	if (DIGITAL_DRV_CAPS_IN_CRC(ddev)) {
370 		rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
371 				NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A);
372 		if (rc)
373 			goto exit;
374 	} else {
375 		digital_skb_add_crc_a(skb);
376 	}
377 
378 	rc = digital_in_send_cmd(ddev, skb, 30, digital_in_recv_sel_res,
379 				 target);
380 exit:
381 	if (rc)
382 		kfree_skb(skb);
383 
384 	return rc;
385 }
386 
387 static void digital_in_recv_sdd_res(struct nfc_digital_dev *ddev, void *arg,
388 				    struct sk_buff *resp)
389 {
390 	struct nfc_target *target = arg;
391 	struct digital_sdd_res *sdd_res;
392 	int rc;
393 	u8 offset, size;
394 	u8 i, bcc;
395 
396 	if (IS_ERR(resp)) {
397 		rc = PTR_ERR(resp);
398 		resp = NULL;
399 		goto exit;
400 	}
401 
402 	if (resp->len < DIGITAL_SDD_RES_LEN) {
403 		PROTOCOL_ERR("4.7.2.8");
404 		rc = -EINVAL;
405 		goto exit;
406 	}
407 
408 	sdd_res = (struct digital_sdd_res *)resp->data;
409 
410 	for (i = 0, bcc = 0; i < 4; i++)
411 		bcc ^= sdd_res->nfcid1[i];
412 
413 	if (bcc != sdd_res->bcc) {
414 		PROTOCOL_ERR("4.7.2.6");
415 		rc = -EINVAL;
416 		goto exit;
417 	}
418 
419 	if (sdd_res->nfcid1[0] == DIGITAL_SDD_RES_CT) {
420 		offset = 1;
421 		size = 3;
422 	} else {
423 		offset = 0;
424 		size = 4;
425 	}
426 
427 	if (target->nfcid1_len + size > NFC_NFCID1_MAXSIZE) {
428 		PROTOCOL_ERR("4.7.2.1");
429 		rc = -EPROTO;
430 		goto exit;
431 	}
432 
433 	memcpy(target->nfcid1 + target->nfcid1_len, sdd_res->nfcid1 + offset,
434 	       size);
435 	target->nfcid1_len += size;
436 
437 	rc = digital_in_send_sel_req(ddev, target, sdd_res);
438 
439 exit:
440 	dev_kfree_skb(resp);
441 
442 	if (rc) {
443 		kfree(target);
444 		digital_poll_next_tech(ddev);
445 	}
446 }
447 
448 static int digital_in_send_sdd_req(struct nfc_digital_dev *ddev,
449 				   struct nfc_target *target)
450 {
451 	int rc;
452 	struct sk_buff *skb;
453 	u8 sel_cmd;
454 
455 	rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
456 				     NFC_DIGITAL_FRAMING_NFCA_STANDARD);
457 	if (rc)
458 		return rc;
459 
460 	skb = digital_skb_alloc(ddev, 2);
461 	if (!skb)
462 		return -ENOMEM;
463 
464 	if (target->nfcid1_len == 0)
465 		sel_cmd = DIGITAL_CMD_SEL_REQ_CL1;
466 	else if (target->nfcid1_len == 3)
467 		sel_cmd = DIGITAL_CMD_SEL_REQ_CL2;
468 	else
469 		sel_cmd = DIGITAL_CMD_SEL_REQ_CL3;
470 
471 	skb_put_u8(skb, sel_cmd);
472 	skb_put_u8(skb, DIGITAL_SDD_REQ_SEL_PAR);
473 
474 	rc = digital_in_send_cmd(ddev, skb, 30, digital_in_recv_sdd_res,
475 				 target);
476 	if (rc)
477 		kfree_skb(skb);
478 
479 	return rc;
480 }
481 
482 static void digital_in_recv_sens_res(struct nfc_digital_dev *ddev, void *arg,
483 				     struct sk_buff *resp)
484 {
485 	struct nfc_target *target = NULL;
486 	int rc;
487 
488 	if (IS_ERR(resp)) {
489 		rc = PTR_ERR(resp);
490 		resp = NULL;
491 		goto exit;
492 	}
493 
494 	if (resp->len < sizeof(u16)) {
495 		rc = -EIO;
496 		goto exit;
497 	}
498 
499 	target = kzalloc_obj(struct nfc_target);
500 	if (!target) {
501 		rc = -ENOMEM;
502 		goto exit;
503 	}
504 
505 	target->sens_res = __le16_to_cpu(*(__le16 *)resp->data);
506 
507 	if (!DIGITAL_SENS_RES_IS_VALID(target->sens_res)) {
508 		PROTOCOL_ERR("4.6.3.3");
509 		rc = -EINVAL;
510 		goto exit;
511 	}
512 
513 	if (DIGITAL_SENS_RES_IS_T1T(target->sens_res))
514 		rc = digital_target_found(ddev, target, NFC_PROTO_JEWEL);
515 	else
516 		rc = digital_in_send_sdd_req(ddev, target);
517 
518 exit:
519 	dev_kfree_skb(resp);
520 
521 	if (rc) {
522 		kfree(target);
523 		digital_poll_next_tech(ddev);
524 	}
525 }
526 
527 int digital_in_send_sens_req(struct nfc_digital_dev *ddev, u8 rf_tech)
528 {
529 	struct sk_buff *skb;
530 	int rc;
531 
532 	rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH,
533 				     NFC_DIGITAL_RF_TECH_106A);
534 	if (rc)
535 		return rc;
536 
537 	rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
538 				     NFC_DIGITAL_FRAMING_NFCA_SHORT);
539 	if (rc)
540 		return rc;
541 
542 	skb = digital_skb_alloc(ddev, 1);
543 	if (!skb)
544 		return -ENOMEM;
545 
546 	skb_put_u8(skb, DIGITAL_CMD_SENS_REQ);
547 
548 	rc = digital_in_send_cmd(ddev, skb, 30, digital_in_recv_sens_res, NULL);
549 	if (rc)
550 		kfree_skb(skb);
551 
552 	return rc;
553 }
554 
555 int digital_in_recv_mifare_res(struct sk_buff *resp)
556 {
557 	/* Successful READ command response is 16 data bytes + 2 CRC bytes long.
558 	 * Since the driver can't differentiate a ACK/NACK response from a valid
559 	 * READ response, the CRC calculation must be handled at digital level
560 	 * even if the driver supports it for this technology.
561 	 */
562 	if (resp->len == DIGITAL_MIFARE_READ_RES_LEN + DIGITAL_CRC_LEN) {
563 		if (digital_skb_check_crc_a(resp)) {
564 			PROTOCOL_ERR("9.4.1.2");
565 			return -EIO;
566 		}
567 
568 		return 0;
569 	}
570 
571 	/* ACK response (i.e. successful WRITE). */
572 	if (resp->len == 1 && resp->data[0] == DIGITAL_MIFARE_ACK_RES) {
573 		resp->data[0] = 0;
574 		return 0;
575 	}
576 
577 	/* NACK and any other responses are treated as error. */
578 	return -EIO;
579 }
580 
581 static void digital_in_recv_attrib_res(struct nfc_digital_dev *ddev, void *arg,
582 				       struct sk_buff *resp)
583 {
584 	struct nfc_target *target = arg;
585 	struct digital_attrib_res *attrib_res;
586 	int rc;
587 
588 	if (IS_ERR(resp)) {
589 		rc = PTR_ERR(resp);
590 		resp = NULL;
591 		goto exit;
592 	}
593 
594 	if (resp->len < sizeof(*attrib_res)) {
595 		PROTOCOL_ERR("12.6.2");
596 		rc = -EIO;
597 		goto exit;
598 	}
599 
600 	attrib_res = (struct digital_attrib_res *)resp->data;
601 
602 	if (attrib_res->mbli_did & 0x0f) {
603 		PROTOCOL_ERR("12.6.2.1");
604 		rc = -EIO;
605 		goto exit;
606 	}
607 
608 	rc = digital_target_found(ddev, target, NFC_PROTO_ISO14443_B);
609 
610 exit:
611 	dev_kfree_skb(resp);
612 	kfree(target);
613 
614 	if (rc)
615 		digital_poll_next_tech(ddev);
616 }
617 
618 static int digital_in_send_attrib_req(struct nfc_digital_dev *ddev,
619 			       struct nfc_target *target,
620 			       struct digital_sensb_res *sensb_res)
621 {
622 	struct digital_attrib_req *attrib_req;
623 	struct sk_buff *skb;
624 	int rc;
625 
626 	skb = digital_skb_alloc(ddev, sizeof(*attrib_req));
627 	if (!skb)
628 		return -ENOMEM;
629 
630 	attrib_req = skb_put(skb, sizeof(*attrib_req));
631 
632 	attrib_req->cmd = DIGITAL_CMD_ATTRIB_REQ;
633 	memcpy(attrib_req->nfcid0, sensb_res->nfcid0,
634 	       sizeof(attrib_req->nfcid0));
635 	attrib_req->param1 = DIGITAL_ATTRIB_P1_TR0_DEFAULT |
636 			     DIGITAL_ATTRIB_P1_TR1_DEFAULT;
637 	attrib_req->param2 = DIGITAL_ATTRIB_P2_LISTEN_POLL_1 |
638 			     DIGITAL_ATTRIB_P2_POLL_LISTEN_1 |
639 			     DIGITAL_ATTRIB_P2_MAX_FRAME_256;
640 	attrib_req->param3 = sensb_res->proto_info[1] & 0x07;
641 	attrib_req->param4 = DIGITAL_ATTRIB_P4_DID(0);
642 
643 	rc = digital_in_send_cmd(ddev, skb, 30, digital_in_recv_attrib_res,
644 				 target);
645 	if (rc)
646 		kfree_skb(skb);
647 
648 	return rc;
649 }
650 
651 static void digital_in_recv_sensb_res(struct nfc_digital_dev *ddev, void *arg,
652 				      struct sk_buff *resp)
653 {
654 	struct nfc_target *target = NULL;
655 	struct digital_sensb_res *sensb_res;
656 	u8 fsci;
657 	int rc;
658 
659 	if (IS_ERR(resp)) {
660 		rc = PTR_ERR(resp);
661 		resp = NULL;
662 		goto exit;
663 	}
664 
665 	if (resp->len != sizeof(*sensb_res)) {
666 		PROTOCOL_ERR("5.6.2.1");
667 		rc = -EIO;
668 		goto exit;
669 	}
670 
671 	sensb_res = (struct digital_sensb_res *)resp->data;
672 
673 	if (sensb_res->cmd != DIGITAL_CMD_SENSB_RES) {
674 		PROTOCOL_ERR("5.6.2");
675 		rc = -EIO;
676 		goto exit;
677 	}
678 
679 	if (!(sensb_res->proto_info[1] & BIT(0))) {
680 		PROTOCOL_ERR("5.6.2.12");
681 		rc = -EIO;
682 		goto exit;
683 	}
684 
685 	if (sensb_res->proto_info[1] & BIT(3)) {
686 		PROTOCOL_ERR("5.6.2.16");
687 		rc = -EIO;
688 		goto exit;
689 	}
690 
691 	fsci = DIGITAL_SENSB_FSCI(sensb_res->proto_info[1]);
692 	if (fsci >= 8)
693 		ddev->target_fsc = DIGITAL_ATS_MAX_FSC;
694 	else
695 		ddev->target_fsc = digital_ats_fsc[fsci];
696 
697 	target = kzalloc_obj(struct nfc_target);
698 	if (!target) {
699 		rc = -ENOMEM;
700 		goto exit;
701 	}
702 
703 	rc = digital_in_send_attrib_req(ddev, target, sensb_res);
704 
705 exit:
706 	dev_kfree_skb(resp);
707 
708 	if (rc) {
709 		kfree(target);
710 		digital_poll_next_tech(ddev);
711 	}
712 }
713 
714 int digital_in_send_sensb_req(struct nfc_digital_dev *ddev, u8 rf_tech)
715 {
716 	struct digital_sensb_req *sensb_req;
717 	struct sk_buff *skb;
718 	int rc;
719 
720 	rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH,
721 				     NFC_DIGITAL_RF_TECH_106B);
722 	if (rc)
723 		return rc;
724 
725 	rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
726 				     NFC_DIGITAL_FRAMING_NFCB);
727 	if (rc)
728 		return rc;
729 
730 	skb = digital_skb_alloc(ddev, sizeof(*sensb_req));
731 	if (!skb)
732 		return -ENOMEM;
733 
734 	sensb_req = skb_put(skb, sizeof(*sensb_req));
735 
736 	sensb_req->cmd = DIGITAL_CMD_SENSB_REQ;
737 	sensb_req->afi = 0x00; /* All families and sub-families */
738 	sensb_req->param = DIGITAL_SENSB_N(0);
739 
740 	rc = digital_in_send_cmd(ddev, skb, 30, digital_in_recv_sensb_res,
741 				 NULL);
742 	if (rc)
743 		kfree_skb(skb);
744 
745 	return rc;
746 }
747 
748 static void digital_in_recv_sensf_res(struct nfc_digital_dev *ddev, void *arg,
749 				   struct sk_buff *resp)
750 {
751 	int rc;
752 	u8 proto;
753 	struct nfc_target target;
754 	struct digital_sensf_res *sensf_res;
755 
756 	if (IS_ERR(resp)) {
757 		rc = PTR_ERR(resp);
758 		resp = NULL;
759 		goto exit;
760 	}
761 
762 	if (resp->len < DIGITAL_SENSF_RES_MIN_LENGTH) {
763 		rc = -EIO;
764 		goto exit;
765 	}
766 
767 	if (!DIGITAL_DRV_CAPS_IN_CRC(ddev)) {
768 		rc = digital_skb_check_crc_f(resp);
769 		if (rc) {
770 			PROTOCOL_ERR("6.4.1.8");
771 			goto exit;
772 		}
773 	}
774 
775 	skb_pull(resp, 1);
776 
777 	memset(&target, 0, sizeof(struct nfc_target));
778 
779 	sensf_res = (struct digital_sensf_res *)resp->data;
780 
781 	memcpy(target.sensf_res, sensf_res, resp->len);
782 	target.sensf_res_len = resp->len;
783 
784 	memcpy(target.nfcid2, sensf_res->nfcid2, NFC_NFCID2_MAXSIZE);
785 	target.nfcid2_len = NFC_NFCID2_MAXSIZE;
786 
787 	if (target.nfcid2[0] == DIGITAL_SENSF_NFCID2_NFC_DEP_B1 &&
788 	    target.nfcid2[1] == DIGITAL_SENSF_NFCID2_NFC_DEP_B2)
789 		proto = NFC_PROTO_NFC_DEP;
790 	else
791 		proto = NFC_PROTO_FELICA;
792 
793 	rc = digital_target_found(ddev, &target, proto);
794 
795 exit:
796 	dev_kfree_skb(resp);
797 
798 	if (rc)
799 		digital_poll_next_tech(ddev);
800 }
801 
802 int digital_in_send_sensf_req(struct nfc_digital_dev *ddev, u8 rf_tech)
803 {
804 	struct digital_sensf_req *sensf_req;
805 	struct sk_buff *skb;
806 	int rc;
807 	u8 size;
808 
809 	rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH, rf_tech);
810 	if (rc)
811 		return rc;
812 
813 	rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
814 				     NFC_DIGITAL_FRAMING_NFCF);
815 	if (rc)
816 		return rc;
817 
818 	size = sizeof(struct digital_sensf_req);
819 
820 	skb = digital_skb_alloc(ddev, size);
821 	if (!skb)
822 		return -ENOMEM;
823 
824 	skb_put(skb, size);
825 
826 	sensf_req = (struct digital_sensf_req *)skb->data;
827 	sensf_req->cmd = DIGITAL_CMD_SENSF_REQ;
828 	sensf_req->sc1 = 0xFF;
829 	sensf_req->sc2 = 0xFF;
830 	sensf_req->rc = 0;
831 	sensf_req->tsn = 0;
832 
833 	*(u8 *)skb_push(skb, 1) = size + 1;
834 
835 	if (!DIGITAL_DRV_CAPS_IN_CRC(ddev))
836 		digital_skb_add_crc_f(skb);
837 
838 	rc = digital_in_send_cmd(ddev, skb, 30, digital_in_recv_sensf_res,
839 				 NULL);
840 	if (rc)
841 		kfree_skb(skb);
842 
843 	return rc;
844 }
845 
846 static void digital_in_recv_iso15693_inv_res(struct nfc_digital_dev *ddev,
847 		void *arg, struct sk_buff *resp)
848 {
849 	struct digital_iso15693_inv_res *res;
850 	struct nfc_target *target = NULL;
851 	int rc;
852 
853 	if (IS_ERR(resp)) {
854 		rc = PTR_ERR(resp);
855 		resp = NULL;
856 		goto out_free_skb;
857 	}
858 
859 	if (resp->len != sizeof(*res)) {
860 		rc = -EIO;
861 		goto out_free_skb;
862 	}
863 
864 	res = (struct digital_iso15693_inv_res *)resp->data;
865 
866 	if (!DIGITAL_ISO15693_RES_IS_VALID(res->flags)) {
867 		PROTOCOL_ERR("ISO15693 - 10.3.1");
868 		rc = -EINVAL;
869 		goto out_free_skb;
870 	}
871 
872 	target = kzalloc_obj(*target);
873 	if (!target) {
874 		rc = -ENOMEM;
875 		goto out_free_skb;
876 	}
877 
878 	target->is_iso15693 = 1;
879 	target->iso15693_dsfid = res->dsfid;
880 	memcpy(target->iso15693_uid, &res->uid, sizeof(target->iso15693_uid));
881 
882 	rc = digital_target_found(ddev, target, NFC_PROTO_ISO15693);
883 
884 	kfree(target);
885 
886 out_free_skb:
887 	dev_kfree_skb(resp);
888 
889 	if (rc)
890 		digital_poll_next_tech(ddev);
891 }
892 
893 int digital_in_send_iso15693_inv_req(struct nfc_digital_dev *ddev, u8 rf_tech)
894 {
895 	struct digital_iso15693_inv_req *req;
896 	struct sk_buff *skb;
897 	int rc;
898 
899 	rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH,
900 				     NFC_DIGITAL_RF_TECH_ISO15693);
901 	if (rc)
902 		return rc;
903 
904 	rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
905 				     NFC_DIGITAL_FRAMING_ISO15693_INVENTORY);
906 	if (rc)
907 		return rc;
908 
909 	skb = digital_skb_alloc(ddev, sizeof(*req));
910 	if (!skb)
911 		return -ENOMEM;
912 
913 	skb_put(skb, sizeof(*req) - sizeof(req->mask)); /* No mask */
914 	req = (struct digital_iso15693_inv_req *)skb->data;
915 
916 	/* Single sub-carrier, high data rate, no AFI, single slot
917 	 * Inventory command
918 	 */
919 	req->flags = DIGITAL_ISO15693_REQ_FLAG_DATA_RATE |
920 		     DIGITAL_ISO15693_REQ_FLAG_INVENTORY |
921 		     DIGITAL_ISO15693_REQ_FLAG_NB_SLOTS;
922 	req->cmd = DIGITAL_CMD_ISO15693_INVENTORY_REQ;
923 	req->mask_len = 0;
924 
925 	rc = digital_in_send_cmd(ddev, skb, 30,
926 				 digital_in_recv_iso15693_inv_res, NULL);
927 	if (rc)
928 		kfree_skb(skb);
929 
930 	return rc;
931 }
932 
933 static int digital_tg_send_sel_res(struct nfc_digital_dev *ddev)
934 {
935 	struct sk_buff *skb;
936 	int rc;
937 
938 	skb = digital_skb_alloc(ddev, 1);
939 	if (!skb)
940 		return -ENOMEM;
941 
942 	skb_put_u8(skb, DIGITAL_SEL_RES_NFC_DEP);
943 
944 	if (!DIGITAL_DRV_CAPS_TG_CRC(ddev))
945 		digital_skb_add_crc_a(skb);
946 
947 	rc = digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
948 				     NFC_DIGITAL_FRAMING_NFCA_ANTICOL_COMPLETE);
949 	if (rc) {
950 		kfree_skb(skb);
951 		return rc;
952 	}
953 
954 	rc = digital_tg_send_cmd(ddev, skb, 300, digital_tg_recv_atr_req,
955 				 NULL);
956 	if (rc)
957 		kfree_skb(skb);
958 
959 	return rc;
960 }
961 
962 static void digital_tg_recv_sel_req(struct nfc_digital_dev *ddev, void *arg,
963 				    struct sk_buff *resp)
964 {
965 	int rc;
966 
967 	if (IS_ERR(resp)) {
968 		rc = PTR_ERR(resp);
969 		resp = NULL;
970 		goto exit;
971 	}
972 
973 	if (!DIGITAL_DRV_CAPS_TG_CRC(ddev)) {
974 		rc = digital_skb_check_crc_a(resp);
975 		if (rc) {
976 			PROTOCOL_ERR("4.4.1.3");
977 			goto exit;
978 		}
979 	}
980 
981 	/* Silently ignore SEL_REQ content and send a SEL_RES for NFC-DEP */
982 
983 	rc = digital_tg_send_sel_res(ddev);
984 
985 exit:
986 	if (rc)
987 		digital_poll_next_tech(ddev);
988 
989 	dev_kfree_skb(resp);
990 }
991 
992 static int digital_tg_send_sdd_res(struct nfc_digital_dev *ddev)
993 {
994 	struct sk_buff *skb;
995 	struct digital_sdd_res *sdd_res;
996 	int rc, i;
997 
998 	skb = digital_skb_alloc(ddev, sizeof(struct digital_sdd_res));
999 	if (!skb)
1000 		return -ENOMEM;
1001 
1002 	skb_put(skb, sizeof(struct digital_sdd_res));
1003 	sdd_res = (struct digital_sdd_res *)skb->data;
1004 
1005 	sdd_res->nfcid1[0] = 0x08;
1006 	get_random_bytes(sdd_res->nfcid1 + 1, 3);
1007 
1008 	sdd_res->bcc = 0;
1009 	for (i = 0; i < 4; i++)
1010 		sdd_res->bcc ^= sdd_res->nfcid1[i];
1011 
1012 	rc = digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
1013 				NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A);
1014 	if (rc) {
1015 		kfree_skb(skb);
1016 		return rc;
1017 	}
1018 
1019 	rc = digital_tg_send_cmd(ddev, skb, 300, digital_tg_recv_sel_req,
1020 				 NULL);
1021 	if (rc)
1022 		kfree_skb(skb);
1023 
1024 	return rc;
1025 }
1026 
1027 static void digital_tg_recv_sdd_req(struct nfc_digital_dev *ddev, void *arg,
1028 				    struct sk_buff *resp)
1029 {
1030 	u8 *sdd_req;
1031 	int rc;
1032 
1033 	if (IS_ERR(resp)) {
1034 		rc = PTR_ERR(resp);
1035 		resp = NULL;
1036 		goto exit;
1037 	}
1038 
1039 	sdd_req = resp->data;
1040 
1041 	if (resp->len < 2 || sdd_req[0] != DIGITAL_CMD_SEL_REQ_CL1 ||
1042 	    sdd_req[1] != DIGITAL_SDD_REQ_SEL_PAR) {
1043 		rc = -EINVAL;
1044 		goto exit;
1045 	}
1046 
1047 	rc = digital_tg_send_sdd_res(ddev);
1048 
1049 exit:
1050 	if (rc)
1051 		digital_poll_next_tech(ddev);
1052 
1053 	dev_kfree_skb(resp);
1054 }
1055 
1056 static int digital_tg_send_sens_res(struct nfc_digital_dev *ddev)
1057 {
1058 	struct sk_buff *skb;
1059 	u8 *sens_res;
1060 	int rc;
1061 
1062 	skb = digital_skb_alloc(ddev, 2);
1063 	if (!skb)
1064 		return -ENOMEM;
1065 
1066 	sens_res = skb_put(skb, 2);
1067 
1068 	sens_res[0] = (DIGITAL_SENS_RES_NFC_DEP >> 8) & 0xFF;
1069 	sens_res[1] = DIGITAL_SENS_RES_NFC_DEP & 0xFF;
1070 
1071 	rc = digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
1072 				     NFC_DIGITAL_FRAMING_NFCA_STANDARD);
1073 	if (rc) {
1074 		kfree_skb(skb);
1075 		return rc;
1076 	}
1077 
1078 	rc = digital_tg_send_cmd(ddev, skb, 300, digital_tg_recv_sdd_req,
1079 				 NULL);
1080 	if (rc)
1081 		kfree_skb(skb);
1082 
1083 	return rc;
1084 }
1085 
1086 void digital_tg_recv_sens_req(struct nfc_digital_dev *ddev, void *arg,
1087 			      struct sk_buff *resp)
1088 {
1089 	u8 sens_req;
1090 	int rc;
1091 
1092 	if (IS_ERR(resp)) {
1093 		rc = PTR_ERR(resp);
1094 		resp = NULL;
1095 		goto exit;
1096 	}
1097 
1098 	sens_req = resp->data[0];
1099 
1100 	if (!resp->len || (sens_req != DIGITAL_CMD_SENS_REQ &&
1101 	    sens_req != DIGITAL_CMD_ALL_REQ)) {
1102 		rc = -EINVAL;
1103 		goto exit;
1104 	}
1105 
1106 	rc = digital_tg_send_sens_res(ddev);
1107 
1108 exit:
1109 	if (rc)
1110 		digital_poll_next_tech(ddev);
1111 
1112 	dev_kfree_skb(resp);
1113 }
1114 
1115 static void digital_tg_recv_atr_or_sensf_req(struct nfc_digital_dev *ddev,
1116 		void *arg, struct sk_buff *resp)
1117 {
1118 	if (!IS_ERR(resp) && (resp->len >= 2) &&
1119 			(resp->data[1] == DIGITAL_CMD_SENSF_REQ))
1120 		digital_tg_recv_sensf_req(ddev, arg, resp);
1121 	else
1122 		digital_tg_recv_atr_req(ddev, arg, resp);
1123 
1124 	return;
1125 }
1126 
1127 static int digital_tg_send_sensf_res(struct nfc_digital_dev *ddev,
1128 			      struct digital_sensf_req *sensf_req)
1129 {
1130 	struct sk_buff *skb;
1131 	u8 size;
1132 	int rc;
1133 	struct digital_sensf_res *sensf_res;
1134 
1135 	size = sizeof(struct digital_sensf_res);
1136 
1137 	if (sensf_req->rc == DIGITAL_SENSF_REQ_RC_NONE)
1138 		size -= sizeof(sensf_res->rd);
1139 
1140 	skb = digital_skb_alloc(ddev, size);
1141 	if (!skb)
1142 		return -ENOMEM;
1143 
1144 	skb_put(skb, size);
1145 
1146 	sensf_res = (struct digital_sensf_res *)skb->data;
1147 
1148 	memset(sensf_res, 0, size);
1149 
1150 	sensf_res->cmd = DIGITAL_CMD_SENSF_RES;
1151 	sensf_res->nfcid2[0] = DIGITAL_SENSF_NFCID2_NFC_DEP_B1;
1152 	sensf_res->nfcid2[1] = DIGITAL_SENSF_NFCID2_NFC_DEP_B2;
1153 	get_random_bytes(&sensf_res->nfcid2[2], 6);
1154 
1155 	switch (sensf_req->rc) {
1156 	case DIGITAL_SENSF_REQ_RC_SC:
1157 		sensf_res->rd[0] = sensf_req->sc1;
1158 		sensf_res->rd[1] = sensf_req->sc2;
1159 		break;
1160 	case DIGITAL_SENSF_REQ_RC_AP:
1161 		sensf_res->rd[0] = DIGITAL_SENSF_RES_RD_AP_B1;
1162 		sensf_res->rd[1] = DIGITAL_SENSF_RES_RD_AP_B2;
1163 		break;
1164 	}
1165 
1166 	*(u8 *)skb_push(skb, sizeof(u8)) = size + 1;
1167 
1168 	if (!DIGITAL_DRV_CAPS_TG_CRC(ddev))
1169 		digital_skb_add_crc_f(skb);
1170 
1171 	rc = digital_tg_send_cmd(ddev, skb, 300,
1172 				 digital_tg_recv_atr_or_sensf_req, NULL);
1173 	if (rc)
1174 		kfree_skb(skb);
1175 
1176 	return rc;
1177 }
1178 
1179 void digital_tg_recv_sensf_req(struct nfc_digital_dev *ddev, void *arg,
1180 			       struct sk_buff *resp)
1181 {
1182 	struct digital_sensf_req *sensf_req;
1183 	int rc;
1184 
1185 	if (IS_ERR(resp)) {
1186 		rc = PTR_ERR(resp);
1187 		resp = NULL;
1188 		goto exit;
1189 	}
1190 
1191 	if (!DIGITAL_DRV_CAPS_TG_CRC(ddev)) {
1192 		rc = digital_skb_check_crc_f(resp);
1193 		if (rc) {
1194 			PROTOCOL_ERR("6.4.1.8");
1195 			goto exit;
1196 		}
1197 	}
1198 
1199 	if (resp->len != sizeof(struct digital_sensf_req) + 1) {
1200 		rc = -EINVAL;
1201 		goto exit;
1202 	}
1203 
1204 	skb_pull(resp, 1);
1205 	sensf_req = (struct digital_sensf_req *)resp->data;
1206 
1207 	if (sensf_req->cmd != DIGITAL_CMD_SENSF_REQ) {
1208 		rc = -EINVAL;
1209 		goto exit;
1210 	}
1211 
1212 	rc = digital_tg_send_sensf_res(ddev, sensf_req);
1213 
1214 exit:
1215 	if (rc)
1216 		digital_poll_next_tech(ddev);
1217 
1218 	dev_kfree_skb(resp);
1219 }
1220 
1221 static int digital_tg_config_nfca(struct nfc_digital_dev *ddev)
1222 {
1223 	int rc;
1224 
1225 	rc = digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH,
1226 				     NFC_DIGITAL_RF_TECH_106A);
1227 	if (rc)
1228 		return rc;
1229 
1230 	return digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
1231 				       NFC_DIGITAL_FRAMING_NFCA_NFC_DEP);
1232 }
1233 
1234 int digital_tg_listen_nfca(struct nfc_digital_dev *ddev, u8 rf_tech)
1235 {
1236 	int rc;
1237 
1238 	rc = digital_tg_config_nfca(ddev);
1239 	if (rc)
1240 		return rc;
1241 
1242 	return digital_tg_listen(ddev, 300, digital_tg_recv_sens_req, NULL);
1243 }
1244 
1245 static int digital_tg_config_nfcf(struct nfc_digital_dev *ddev, u8 rf_tech)
1246 {
1247 	int rc;
1248 
1249 	rc = digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH, rf_tech);
1250 	if (rc)
1251 		return rc;
1252 
1253 	return digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
1254 				       NFC_DIGITAL_FRAMING_NFCF_NFC_DEP);
1255 }
1256 
1257 int digital_tg_listen_nfcf(struct nfc_digital_dev *ddev, u8 rf_tech)
1258 {
1259 	int rc;
1260 
1261 	rc = digital_tg_config_nfcf(ddev, rf_tech);
1262 	if (rc)
1263 		return rc;
1264 
1265 	return digital_tg_listen(ddev, 300, digital_tg_recv_sensf_req, NULL);
1266 }
1267 
1268 void digital_tg_recv_md_req(struct nfc_digital_dev *ddev, void *arg,
1269 			    struct sk_buff *resp)
1270 {
1271 	u8 rf_tech;
1272 	int rc;
1273 
1274 	if (IS_ERR(resp)) {
1275 		resp = NULL;
1276 		goto exit_free_skb;
1277 	}
1278 
1279 	rc = ddev->ops->tg_get_rf_tech(ddev, &rf_tech);
1280 	if (rc)
1281 		goto exit_free_skb;
1282 
1283 	switch (rf_tech) {
1284 	case NFC_DIGITAL_RF_TECH_106A:
1285 		rc = digital_tg_config_nfca(ddev);
1286 		if (rc)
1287 			goto exit_free_skb;
1288 		digital_tg_recv_sens_req(ddev, arg, resp);
1289 		break;
1290 	case NFC_DIGITAL_RF_TECH_212F:
1291 	case NFC_DIGITAL_RF_TECH_424F:
1292 		rc = digital_tg_config_nfcf(ddev, rf_tech);
1293 		if (rc)
1294 			goto exit_free_skb;
1295 		digital_tg_recv_sensf_req(ddev, arg, resp);
1296 		break;
1297 	default:
1298 		goto exit_free_skb;
1299 	}
1300 
1301 	return;
1302 
1303 exit_free_skb:
1304 	digital_poll_next_tech(ddev);
1305 	dev_kfree_skb(resp);
1306 }
1307