xref: /linux/net/nfc/digital_technology.c (revision 33f016b23a219fe034213849b51436b8e79df251)
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 	resp->len = min_t(unsigned int, resp->len, NFC_SENSF_RES_MAXSIZE);
782 
783 	memcpy(target.sensf_res, sensf_res, resp->len);
784 	target.sensf_res_len = resp->len;
785 
786 	memcpy(target.nfcid2, sensf_res->nfcid2, NFC_NFCID2_MAXSIZE);
787 	target.nfcid2_len = NFC_NFCID2_MAXSIZE;
788 
789 	if (target.nfcid2[0] == DIGITAL_SENSF_NFCID2_NFC_DEP_B1 &&
790 	    target.nfcid2[1] == DIGITAL_SENSF_NFCID2_NFC_DEP_B2)
791 		proto = NFC_PROTO_NFC_DEP;
792 	else
793 		proto = NFC_PROTO_FELICA;
794 
795 	rc = digital_target_found(ddev, &target, proto);
796 
797 exit:
798 	dev_kfree_skb(resp);
799 
800 	if (rc)
801 		digital_poll_next_tech(ddev);
802 }
803 
804 int digital_in_send_sensf_req(struct nfc_digital_dev *ddev, u8 rf_tech)
805 {
806 	struct digital_sensf_req *sensf_req;
807 	struct sk_buff *skb;
808 	int rc;
809 	u8 size;
810 
811 	rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH, rf_tech);
812 	if (rc)
813 		return rc;
814 
815 	rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
816 				     NFC_DIGITAL_FRAMING_NFCF);
817 	if (rc)
818 		return rc;
819 
820 	size = sizeof(struct digital_sensf_req);
821 
822 	skb = digital_skb_alloc(ddev, size);
823 	if (!skb)
824 		return -ENOMEM;
825 
826 	skb_put(skb, size);
827 
828 	sensf_req = (struct digital_sensf_req *)skb->data;
829 	sensf_req->cmd = DIGITAL_CMD_SENSF_REQ;
830 	sensf_req->sc1 = 0xFF;
831 	sensf_req->sc2 = 0xFF;
832 	sensf_req->rc = 0;
833 	sensf_req->tsn = 0;
834 
835 	*(u8 *)skb_push(skb, 1) = size + 1;
836 
837 	if (!DIGITAL_DRV_CAPS_IN_CRC(ddev))
838 		digital_skb_add_crc_f(skb);
839 
840 	rc = digital_in_send_cmd(ddev, skb, 30, digital_in_recv_sensf_res,
841 				 NULL);
842 	if (rc)
843 		kfree_skb(skb);
844 
845 	return rc;
846 }
847 
848 static void digital_in_recv_iso15693_inv_res(struct nfc_digital_dev *ddev,
849 		void *arg, struct sk_buff *resp)
850 {
851 	struct digital_iso15693_inv_res *res;
852 	struct nfc_target *target = NULL;
853 	int rc;
854 
855 	if (IS_ERR(resp)) {
856 		rc = PTR_ERR(resp);
857 		resp = NULL;
858 		goto out_free_skb;
859 	}
860 
861 	if (resp->len != sizeof(*res)) {
862 		rc = -EIO;
863 		goto out_free_skb;
864 	}
865 
866 	res = (struct digital_iso15693_inv_res *)resp->data;
867 
868 	if (!DIGITAL_ISO15693_RES_IS_VALID(res->flags)) {
869 		PROTOCOL_ERR("ISO15693 - 10.3.1");
870 		rc = -EINVAL;
871 		goto out_free_skb;
872 	}
873 
874 	target = kzalloc_obj(*target);
875 	if (!target) {
876 		rc = -ENOMEM;
877 		goto out_free_skb;
878 	}
879 
880 	target->is_iso15693 = 1;
881 	target->iso15693_dsfid = res->dsfid;
882 	memcpy(target->iso15693_uid, &res->uid, sizeof(target->iso15693_uid));
883 
884 	rc = digital_target_found(ddev, target, NFC_PROTO_ISO15693);
885 
886 	kfree(target);
887 
888 out_free_skb:
889 	dev_kfree_skb(resp);
890 
891 	if (rc)
892 		digital_poll_next_tech(ddev);
893 }
894 
895 int digital_in_send_iso15693_inv_req(struct nfc_digital_dev *ddev, u8 rf_tech)
896 {
897 	struct digital_iso15693_inv_req *req;
898 	struct sk_buff *skb;
899 	int rc;
900 
901 	rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH,
902 				     NFC_DIGITAL_RF_TECH_ISO15693);
903 	if (rc)
904 		return rc;
905 
906 	rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
907 				     NFC_DIGITAL_FRAMING_ISO15693_INVENTORY);
908 	if (rc)
909 		return rc;
910 
911 	skb = digital_skb_alloc(ddev, sizeof(*req));
912 	if (!skb)
913 		return -ENOMEM;
914 
915 	skb_put(skb, sizeof(*req) - sizeof(req->mask)); /* No mask */
916 	req = (struct digital_iso15693_inv_req *)skb->data;
917 
918 	/* Single sub-carrier, high data rate, no AFI, single slot
919 	 * Inventory command
920 	 */
921 	req->flags = DIGITAL_ISO15693_REQ_FLAG_DATA_RATE |
922 		     DIGITAL_ISO15693_REQ_FLAG_INVENTORY |
923 		     DIGITAL_ISO15693_REQ_FLAG_NB_SLOTS;
924 	req->cmd = DIGITAL_CMD_ISO15693_INVENTORY_REQ;
925 	req->mask_len = 0;
926 
927 	rc = digital_in_send_cmd(ddev, skb, 30,
928 				 digital_in_recv_iso15693_inv_res, NULL);
929 	if (rc)
930 		kfree_skb(skb);
931 
932 	return rc;
933 }
934 
935 static int digital_tg_send_sel_res(struct nfc_digital_dev *ddev)
936 {
937 	struct sk_buff *skb;
938 	int rc;
939 
940 	skb = digital_skb_alloc(ddev, 1);
941 	if (!skb)
942 		return -ENOMEM;
943 
944 	skb_put_u8(skb, DIGITAL_SEL_RES_NFC_DEP);
945 
946 	if (!DIGITAL_DRV_CAPS_TG_CRC(ddev))
947 		digital_skb_add_crc_a(skb);
948 
949 	rc = digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
950 				     NFC_DIGITAL_FRAMING_NFCA_ANTICOL_COMPLETE);
951 	if (rc) {
952 		kfree_skb(skb);
953 		return rc;
954 	}
955 
956 	rc = digital_tg_send_cmd(ddev, skb, 300, digital_tg_recv_atr_req,
957 				 NULL);
958 	if (rc)
959 		kfree_skb(skb);
960 
961 	return rc;
962 }
963 
964 static void digital_tg_recv_sel_req(struct nfc_digital_dev *ddev, void *arg,
965 				    struct sk_buff *resp)
966 {
967 	int rc;
968 
969 	if (IS_ERR(resp)) {
970 		rc = PTR_ERR(resp);
971 		resp = NULL;
972 		goto exit;
973 	}
974 
975 	if (!DIGITAL_DRV_CAPS_TG_CRC(ddev)) {
976 		rc = digital_skb_check_crc_a(resp);
977 		if (rc) {
978 			PROTOCOL_ERR("4.4.1.3");
979 			goto exit;
980 		}
981 	}
982 
983 	/* Silently ignore SEL_REQ content and send a SEL_RES for NFC-DEP */
984 
985 	rc = digital_tg_send_sel_res(ddev);
986 
987 exit:
988 	if (rc)
989 		digital_poll_next_tech(ddev);
990 
991 	dev_kfree_skb(resp);
992 }
993 
994 static int digital_tg_send_sdd_res(struct nfc_digital_dev *ddev)
995 {
996 	struct sk_buff *skb;
997 	struct digital_sdd_res *sdd_res;
998 	int rc, i;
999 
1000 	skb = digital_skb_alloc(ddev, sizeof(struct digital_sdd_res));
1001 	if (!skb)
1002 		return -ENOMEM;
1003 
1004 	skb_put(skb, sizeof(struct digital_sdd_res));
1005 	sdd_res = (struct digital_sdd_res *)skb->data;
1006 
1007 	sdd_res->nfcid1[0] = 0x08;
1008 	get_random_bytes(sdd_res->nfcid1 + 1, 3);
1009 
1010 	sdd_res->bcc = 0;
1011 	for (i = 0; i < 4; i++)
1012 		sdd_res->bcc ^= sdd_res->nfcid1[i];
1013 
1014 	rc = digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
1015 				NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A);
1016 	if (rc) {
1017 		kfree_skb(skb);
1018 		return rc;
1019 	}
1020 
1021 	rc = digital_tg_send_cmd(ddev, skb, 300, digital_tg_recv_sel_req,
1022 				 NULL);
1023 	if (rc)
1024 		kfree_skb(skb);
1025 
1026 	return rc;
1027 }
1028 
1029 static void digital_tg_recv_sdd_req(struct nfc_digital_dev *ddev, void *arg,
1030 				    struct sk_buff *resp)
1031 {
1032 	u8 *sdd_req;
1033 	int rc;
1034 
1035 	if (IS_ERR(resp)) {
1036 		rc = PTR_ERR(resp);
1037 		resp = NULL;
1038 		goto exit;
1039 	}
1040 
1041 	sdd_req = resp->data;
1042 
1043 	if (resp->len < 2 || sdd_req[0] != DIGITAL_CMD_SEL_REQ_CL1 ||
1044 	    sdd_req[1] != DIGITAL_SDD_REQ_SEL_PAR) {
1045 		rc = -EINVAL;
1046 		goto exit;
1047 	}
1048 
1049 	rc = digital_tg_send_sdd_res(ddev);
1050 
1051 exit:
1052 	if (rc)
1053 		digital_poll_next_tech(ddev);
1054 
1055 	dev_kfree_skb(resp);
1056 }
1057 
1058 static int digital_tg_send_sens_res(struct nfc_digital_dev *ddev)
1059 {
1060 	struct sk_buff *skb;
1061 	u8 *sens_res;
1062 	int rc;
1063 
1064 	skb = digital_skb_alloc(ddev, 2);
1065 	if (!skb)
1066 		return -ENOMEM;
1067 
1068 	sens_res = skb_put(skb, 2);
1069 
1070 	sens_res[0] = (DIGITAL_SENS_RES_NFC_DEP >> 8) & 0xFF;
1071 	sens_res[1] = DIGITAL_SENS_RES_NFC_DEP & 0xFF;
1072 
1073 	rc = digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
1074 				     NFC_DIGITAL_FRAMING_NFCA_STANDARD);
1075 	if (rc) {
1076 		kfree_skb(skb);
1077 		return rc;
1078 	}
1079 
1080 	rc = digital_tg_send_cmd(ddev, skb, 300, digital_tg_recv_sdd_req,
1081 				 NULL);
1082 	if (rc)
1083 		kfree_skb(skb);
1084 
1085 	return rc;
1086 }
1087 
1088 void digital_tg_recv_sens_req(struct nfc_digital_dev *ddev, void *arg,
1089 			      struct sk_buff *resp)
1090 {
1091 	u8 sens_req;
1092 	int rc;
1093 
1094 	if (IS_ERR(resp)) {
1095 		rc = PTR_ERR(resp);
1096 		resp = NULL;
1097 		goto exit;
1098 	}
1099 
1100 	sens_req = resp->data[0];
1101 
1102 	if (!resp->len || (sens_req != DIGITAL_CMD_SENS_REQ &&
1103 	    sens_req != DIGITAL_CMD_ALL_REQ)) {
1104 		rc = -EINVAL;
1105 		goto exit;
1106 	}
1107 
1108 	rc = digital_tg_send_sens_res(ddev);
1109 
1110 exit:
1111 	if (rc)
1112 		digital_poll_next_tech(ddev);
1113 
1114 	dev_kfree_skb(resp);
1115 }
1116 
1117 static void digital_tg_recv_atr_or_sensf_req(struct nfc_digital_dev *ddev,
1118 		void *arg, struct sk_buff *resp)
1119 {
1120 	if (!IS_ERR(resp) && (resp->len >= 2) &&
1121 			(resp->data[1] == DIGITAL_CMD_SENSF_REQ))
1122 		digital_tg_recv_sensf_req(ddev, arg, resp);
1123 	else
1124 		digital_tg_recv_atr_req(ddev, arg, resp);
1125 
1126 	return;
1127 }
1128 
1129 static int digital_tg_send_sensf_res(struct nfc_digital_dev *ddev,
1130 			      struct digital_sensf_req *sensf_req)
1131 {
1132 	struct sk_buff *skb;
1133 	u8 size;
1134 	int rc;
1135 	struct digital_sensf_res *sensf_res;
1136 
1137 	size = sizeof(struct digital_sensf_res);
1138 
1139 	if (sensf_req->rc == DIGITAL_SENSF_REQ_RC_NONE)
1140 		size -= sizeof(sensf_res->rd);
1141 
1142 	skb = digital_skb_alloc(ddev, size);
1143 	if (!skb)
1144 		return -ENOMEM;
1145 
1146 	skb_put(skb, size);
1147 
1148 	sensf_res = (struct digital_sensf_res *)skb->data;
1149 
1150 	memset(sensf_res, 0, size);
1151 
1152 	sensf_res->cmd = DIGITAL_CMD_SENSF_RES;
1153 	sensf_res->nfcid2[0] = DIGITAL_SENSF_NFCID2_NFC_DEP_B1;
1154 	sensf_res->nfcid2[1] = DIGITAL_SENSF_NFCID2_NFC_DEP_B2;
1155 	get_random_bytes(&sensf_res->nfcid2[2], 6);
1156 
1157 	switch (sensf_req->rc) {
1158 	case DIGITAL_SENSF_REQ_RC_SC:
1159 		sensf_res->rd[0] = sensf_req->sc1;
1160 		sensf_res->rd[1] = sensf_req->sc2;
1161 		break;
1162 	case DIGITAL_SENSF_REQ_RC_AP:
1163 		sensf_res->rd[0] = DIGITAL_SENSF_RES_RD_AP_B1;
1164 		sensf_res->rd[1] = DIGITAL_SENSF_RES_RD_AP_B2;
1165 		break;
1166 	}
1167 
1168 	*(u8 *)skb_push(skb, sizeof(u8)) = size + 1;
1169 
1170 	if (!DIGITAL_DRV_CAPS_TG_CRC(ddev))
1171 		digital_skb_add_crc_f(skb);
1172 
1173 	rc = digital_tg_send_cmd(ddev, skb, 300,
1174 				 digital_tg_recv_atr_or_sensf_req, NULL);
1175 	if (rc)
1176 		kfree_skb(skb);
1177 
1178 	return rc;
1179 }
1180 
1181 void digital_tg_recv_sensf_req(struct nfc_digital_dev *ddev, void *arg,
1182 			       struct sk_buff *resp)
1183 {
1184 	struct digital_sensf_req *sensf_req;
1185 	int rc;
1186 
1187 	if (IS_ERR(resp)) {
1188 		rc = PTR_ERR(resp);
1189 		resp = NULL;
1190 		goto exit;
1191 	}
1192 
1193 	if (!DIGITAL_DRV_CAPS_TG_CRC(ddev)) {
1194 		rc = digital_skb_check_crc_f(resp);
1195 		if (rc) {
1196 			PROTOCOL_ERR("6.4.1.8");
1197 			goto exit;
1198 		}
1199 	}
1200 
1201 	if (resp->len != sizeof(struct digital_sensf_req) + 1) {
1202 		rc = -EINVAL;
1203 		goto exit;
1204 	}
1205 
1206 	skb_pull(resp, 1);
1207 	sensf_req = (struct digital_sensf_req *)resp->data;
1208 
1209 	if (sensf_req->cmd != DIGITAL_CMD_SENSF_REQ) {
1210 		rc = -EINVAL;
1211 		goto exit;
1212 	}
1213 
1214 	rc = digital_tg_send_sensf_res(ddev, sensf_req);
1215 
1216 exit:
1217 	if (rc)
1218 		digital_poll_next_tech(ddev);
1219 
1220 	dev_kfree_skb(resp);
1221 }
1222 
1223 static int digital_tg_config_nfca(struct nfc_digital_dev *ddev)
1224 {
1225 	int rc;
1226 
1227 	rc = digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH,
1228 				     NFC_DIGITAL_RF_TECH_106A);
1229 	if (rc)
1230 		return rc;
1231 
1232 	return digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
1233 				       NFC_DIGITAL_FRAMING_NFCA_NFC_DEP);
1234 }
1235 
1236 int digital_tg_listen_nfca(struct nfc_digital_dev *ddev, u8 rf_tech)
1237 {
1238 	int rc;
1239 
1240 	rc = digital_tg_config_nfca(ddev);
1241 	if (rc)
1242 		return rc;
1243 
1244 	return digital_tg_listen(ddev, 300, digital_tg_recv_sens_req, NULL);
1245 }
1246 
1247 static int digital_tg_config_nfcf(struct nfc_digital_dev *ddev, u8 rf_tech)
1248 {
1249 	int rc;
1250 
1251 	rc = digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH, rf_tech);
1252 	if (rc)
1253 		return rc;
1254 
1255 	return digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
1256 				       NFC_DIGITAL_FRAMING_NFCF_NFC_DEP);
1257 }
1258 
1259 int digital_tg_listen_nfcf(struct nfc_digital_dev *ddev, u8 rf_tech)
1260 {
1261 	int rc;
1262 
1263 	rc = digital_tg_config_nfcf(ddev, rf_tech);
1264 	if (rc)
1265 		return rc;
1266 
1267 	return digital_tg_listen(ddev, 300, digital_tg_recv_sensf_req, NULL);
1268 }
1269 
1270 void digital_tg_recv_md_req(struct nfc_digital_dev *ddev, void *arg,
1271 			    struct sk_buff *resp)
1272 {
1273 	u8 rf_tech;
1274 	int rc;
1275 
1276 	if (IS_ERR(resp)) {
1277 		resp = NULL;
1278 		goto exit_free_skb;
1279 	}
1280 
1281 	rc = ddev->ops->tg_get_rf_tech(ddev, &rf_tech);
1282 	if (rc)
1283 		goto exit_free_skb;
1284 
1285 	switch (rf_tech) {
1286 	case NFC_DIGITAL_RF_TECH_106A:
1287 		rc = digital_tg_config_nfca(ddev);
1288 		if (rc)
1289 			goto exit_free_skb;
1290 		digital_tg_recv_sens_req(ddev, arg, resp);
1291 		break;
1292 	case NFC_DIGITAL_RF_TECH_212F:
1293 	case NFC_DIGITAL_RF_TECH_424F:
1294 		rc = digital_tg_config_nfcf(ddev, rf_tech);
1295 		if (rc)
1296 			goto exit_free_skb;
1297 		digital_tg_recv_sensf_req(ddev, arg, resp);
1298 		break;
1299 	default:
1300 		goto exit_free_skb;
1301 	}
1302 
1303 	return;
1304 
1305 exit_free_skb:
1306 	digital_poll_next_tech(ddev);
1307 	dev_kfree_skb(resp);
1308 }
1309