xref: /openbmc/linux/drivers/nfc/st21nfca/dep.c (revision 63705da3)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2014  STMicroelectronics SAS. All rights reserved.
4  */
5 
6 #include <net/nfc/hci.h>
7 
8 #include "st21nfca.h"
9 
10 #define ST21NFCA_NFCIP1_INITIATOR 0x00
11 #define ST21NFCA_NFCIP1_REQ 0xd4
12 #define ST21NFCA_NFCIP1_RES 0xd5
13 #define ST21NFCA_NFCIP1_ATR_REQ 0x00
14 #define ST21NFCA_NFCIP1_ATR_RES 0x01
15 #define ST21NFCA_NFCIP1_PSL_REQ 0x04
16 #define ST21NFCA_NFCIP1_PSL_RES 0x05
17 #define ST21NFCA_NFCIP1_DEP_REQ 0x06
18 #define ST21NFCA_NFCIP1_DEP_RES 0x07
19 
20 #define ST21NFCA_NFC_DEP_PFB_PNI(pfb)     ((pfb) & 0x03)
21 #define ST21NFCA_NFC_DEP_PFB_TYPE(pfb) ((pfb) & 0xE0)
22 #define ST21NFCA_NFC_DEP_PFB_IS_TIMEOUT(pfb) \
23 				((pfb) & ST21NFCA_NFC_DEP_PFB_TIMEOUT_BIT)
24 #define ST21NFCA_NFC_DEP_DID_BIT_SET(pfb) ((pfb) & 0x04)
25 #define ST21NFCA_NFC_DEP_NAD_BIT_SET(pfb) ((pfb) & 0x08)
26 #define ST21NFCA_NFC_DEP_PFB_TIMEOUT_BIT 0x10
27 
28 #define ST21NFCA_NFC_DEP_PFB_IS_TIMEOUT(pfb) \
29 				((pfb) & ST21NFCA_NFC_DEP_PFB_TIMEOUT_BIT)
30 
31 #define ST21NFCA_NFC_DEP_PFB_I_PDU          0x00
32 #define ST21NFCA_NFC_DEP_PFB_ACK_NACK_PDU   0x40
33 #define ST21NFCA_NFC_DEP_PFB_SUPERVISOR_PDU 0x80
34 
35 #define ST21NFCA_ATR_REQ_MIN_SIZE 17
36 #define ST21NFCA_ATR_REQ_MAX_SIZE 65
37 #define ST21NFCA_LR_BITS_PAYLOAD_SIZE_254B 0x30
38 #define ST21NFCA_GB_BIT  0x02
39 
40 #define ST21NFCA_EVT_SEND_DATA		0x10
41 #define ST21NFCA_EVT_FIELD_ON           0x11
42 #define ST21NFCA_EVT_CARD_DEACTIVATED   0x12
43 #define ST21NFCA_EVT_CARD_ACTIVATED     0x13
44 #define ST21NFCA_EVT_FIELD_OFF          0x14
45 
46 #define ST21NFCA_EVT_CARD_F_BITRATE 0x16
47 #define ST21NFCA_EVT_READER_F_BITRATE 0x13
48 #define	ST21NFCA_PSL_REQ_SEND_SPEED(brs) (brs & 0x38)
49 #define ST21NFCA_PSL_REQ_RECV_SPEED(brs) (brs & 0x07)
50 #define ST21NFCA_PP2LRI(pp) ((pp & 0x30) >> 4)
51 #define ST21NFCA_CARD_BITRATE_212 0x01
52 #define ST21NFCA_CARD_BITRATE_424 0x02
53 
54 #define ST21NFCA_DEFAULT_TIMEOUT 0x0a
55 
56 
57 #define PROTOCOL_ERR(req) pr_err("%d: ST21NFCA Protocol error: %s\n", \
58 				 __LINE__, req)
59 
60 struct st21nfca_atr_req {
61 	u8 length;
62 	u8 cmd0;
63 	u8 cmd1;
64 	u8 nfcid3[NFC_NFCID3_MAXSIZE];
65 	u8 did;
66 	u8 bsi;
67 	u8 bri;
68 	u8 ppi;
69 	u8 gbi[];
70 } __packed;
71 
72 struct st21nfca_atr_res {
73 	u8 length;
74 	u8 cmd0;
75 	u8 cmd1;
76 	u8 nfcid3[NFC_NFCID3_MAXSIZE];
77 	u8 did;
78 	u8 bsi;
79 	u8 bri;
80 	u8 to;
81 	u8 ppi;
82 	u8 gbi[];
83 } __packed;
84 
85 struct st21nfca_psl_req {
86 	u8 length;
87 	u8 cmd0;
88 	u8 cmd1;
89 	u8 did;
90 	u8 brs;
91 	u8 fsl;
92 } __packed;
93 
94 struct st21nfca_psl_res {
95 	u8 length;
96 	u8 cmd0;
97 	u8 cmd1;
98 	u8 did;
99 } __packed;
100 
101 struct st21nfca_dep_req_res {
102 	u8 length;
103 	u8 cmd0;
104 	u8 cmd1;
105 	u8 pfb;
106 	u8 did;
107 	u8 nad;
108 } __packed;
109 
110 static void st21nfca_tx_work(struct work_struct *work)
111 {
112 	struct st21nfca_hci_info *info = container_of(work,
113 						struct st21nfca_hci_info,
114 						dep_info.tx_work);
115 
116 	struct nfc_dev *dev;
117 	struct sk_buff *skb;
118 
119 	if (info) {
120 		dev = info->hdev->ndev;
121 		skb = info->dep_info.tx_pending;
122 
123 		device_lock(&dev->dev);
124 
125 		nfc_hci_send_cmd_async(info->hdev, ST21NFCA_RF_READER_F_GATE,
126 				ST21NFCA_WR_XCHG_DATA, skb->data, skb->len,
127 				info->async_cb, info);
128 		device_unlock(&dev->dev);
129 		kfree_skb(skb);
130 	}
131 }
132 
133 static void st21nfca_im_send_pdu(struct st21nfca_hci_info *info,
134 						struct sk_buff *skb)
135 {
136 	info->dep_info.tx_pending = skb;
137 	schedule_work(&info->dep_info.tx_work);
138 }
139 
140 static int st21nfca_tm_send_atr_res(struct nfc_hci_dev *hdev,
141 				    struct st21nfca_atr_req *atr_req)
142 {
143 	struct st21nfca_atr_res *atr_res;
144 	struct sk_buff *skb;
145 	size_t gb_len;
146 	int r;
147 	struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
148 
149 	gb_len = atr_req->length - sizeof(struct st21nfca_atr_req);
150 	skb = alloc_skb(atr_req->length + 1, GFP_KERNEL);
151 	if (!skb)
152 		return -ENOMEM;
153 
154 	skb_put(skb, sizeof(struct st21nfca_atr_res));
155 
156 	atr_res = (struct st21nfca_atr_res *)skb->data;
157 	memset(atr_res, 0, sizeof(struct st21nfca_atr_res));
158 
159 	atr_res->length = atr_req->length + 1;
160 	atr_res->cmd0 = ST21NFCA_NFCIP1_RES;
161 	atr_res->cmd1 = ST21NFCA_NFCIP1_ATR_RES;
162 
163 	memcpy(atr_res->nfcid3, atr_req->nfcid3, 6);
164 	atr_res->bsi = 0x00;
165 	atr_res->bri = 0x00;
166 	atr_res->to = ST21NFCA_DEFAULT_TIMEOUT;
167 	atr_res->ppi = ST21NFCA_LR_BITS_PAYLOAD_SIZE_254B;
168 
169 	if (gb_len) {
170 		skb_put(skb, gb_len);
171 
172 		atr_res->ppi |= ST21NFCA_GB_BIT;
173 		memcpy(atr_res->gbi, atr_req->gbi, gb_len);
174 		r = nfc_set_remote_general_bytes(hdev->ndev, atr_res->gbi,
175 						  gb_len);
176 		if (r < 0) {
177 			kfree_skb(skb);
178 			return r;
179 		}
180 	}
181 
182 	info->dep_info.curr_nfc_dep_pni = 0;
183 
184 	r = nfc_hci_send_event(hdev, ST21NFCA_RF_CARD_F_GATE,
185 				ST21NFCA_EVT_SEND_DATA, skb->data, skb->len);
186 	kfree_skb(skb);
187 	return r;
188 }
189 
190 static int st21nfca_tm_recv_atr_req(struct nfc_hci_dev *hdev,
191 				    struct sk_buff *skb)
192 {
193 	struct st21nfca_atr_req *atr_req;
194 	size_t gb_len;
195 	int r;
196 
197 	skb_trim(skb, skb->len - 1);
198 
199 	if (!skb->len)
200 		return -EIO;
201 
202 	if (skb->len < ST21NFCA_ATR_REQ_MIN_SIZE)
203 		return -EPROTO;
204 
205 	atr_req = (struct st21nfca_atr_req *)skb->data;
206 
207 	if (atr_req->length < sizeof(struct st21nfca_atr_req))
208 		return -EPROTO;
209 
210 	r = st21nfca_tm_send_atr_res(hdev, atr_req);
211 	if (r)
212 		return r;
213 
214 	gb_len = skb->len - sizeof(struct st21nfca_atr_req);
215 
216 	r = nfc_tm_activated(hdev->ndev, NFC_PROTO_NFC_DEP_MASK,
217 			      NFC_COMM_PASSIVE, atr_req->gbi, gb_len);
218 	if (r)
219 		return r;
220 
221 	return 0;
222 }
223 
224 static int st21nfca_tm_send_psl_res(struct nfc_hci_dev *hdev,
225 				    struct st21nfca_psl_req *psl_req)
226 {
227 	struct st21nfca_psl_res *psl_res;
228 	struct sk_buff *skb;
229 	u8 bitrate[2] = {0, 0};
230 	int r;
231 
232 	skb = alloc_skb(sizeof(struct st21nfca_psl_res), GFP_KERNEL);
233 	if (!skb)
234 		return -ENOMEM;
235 	skb_put(skb, sizeof(struct st21nfca_psl_res));
236 
237 	psl_res = (struct st21nfca_psl_res *)skb->data;
238 
239 	psl_res->length = sizeof(struct st21nfca_psl_res);
240 	psl_res->cmd0 = ST21NFCA_NFCIP1_RES;
241 	psl_res->cmd1 = ST21NFCA_NFCIP1_PSL_RES;
242 	psl_res->did = psl_req->did;
243 
244 	r = nfc_hci_send_event(hdev, ST21NFCA_RF_CARD_F_GATE,
245 				ST21NFCA_EVT_SEND_DATA, skb->data, skb->len);
246 	if (r < 0)
247 		goto error;
248 
249 	/*
250 	 * ST21NFCA only support P2P passive.
251 	 * PSL_REQ BRS value != 0 has only a meaning to
252 	 * change technology to type F.
253 	 * We change to BITRATE 424Kbits.
254 	 * In other case switch to BITRATE 106Kbits.
255 	 */
256 	if (ST21NFCA_PSL_REQ_SEND_SPEED(psl_req->brs) &&
257 	    ST21NFCA_PSL_REQ_RECV_SPEED(psl_req->brs)) {
258 		bitrate[0] = ST21NFCA_CARD_BITRATE_424;
259 		bitrate[1] = ST21NFCA_CARD_BITRATE_424;
260 	}
261 
262 	/* Send an event to change bitrate change event to card f */
263 	r = nfc_hci_send_event(hdev, ST21NFCA_RF_CARD_F_GATE,
264 			ST21NFCA_EVT_CARD_F_BITRATE, bitrate, 2);
265 error:
266 	kfree_skb(skb);
267 	return r;
268 }
269 
270 static int st21nfca_tm_recv_psl_req(struct nfc_hci_dev *hdev,
271 				    struct sk_buff *skb)
272 {
273 	struct st21nfca_psl_req *psl_req;
274 
275 	skb_trim(skb, skb->len - 1);
276 
277 	if (!skb->len)
278 		return -EIO;
279 
280 	psl_req = (struct st21nfca_psl_req *)skb->data;
281 
282 	if (skb->len < sizeof(struct st21nfca_psl_req))
283 		return -EIO;
284 
285 	return st21nfca_tm_send_psl_res(hdev, psl_req);
286 }
287 
288 int st21nfca_tm_send_dep_res(struct nfc_hci_dev *hdev, struct sk_buff *skb)
289 {
290 	int r;
291 	struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
292 
293 	*(u8 *)skb_push(skb, 1) = info->dep_info.curr_nfc_dep_pni;
294 	*(u8 *)skb_push(skb, 1) = ST21NFCA_NFCIP1_DEP_RES;
295 	*(u8 *)skb_push(skb, 1) = ST21NFCA_NFCIP1_RES;
296 	*(u8 *)skb_push(skb, 1) = skb->len;
297 
298 	r = nfc_hci_send_event(hdev, ST21NFCA_RF_CARD_F_GATE,
299 			ST21NFCA_EVT_SEND_DATA, skb->data, skb->len);
300 	kfree_skb(skb);
301 
302 	return r;
303 }
304 EXPORT_SYMBOL(st21nfca_tm_send_dep_res);
305 
306 static int st21nfca_tm_recv_dep_req(struct nfc_hci_dev *hdev,
307 				    struct sk_buff *skb)
308 {
309 	struct st21nfca_dep_req_res *dep_req;
310 	u8 size;
311 	struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
312 
313 	skb_trim(skb, skb->len - 1);
314 
315 	size = 4;
316 
317 	dep_req = (struct st21nfca_dep_req_res *)skb->data;
318 	if (skb->len < size)
319 		return -EIO;
320 
321 	if (ST21NFCA_NFC_DEP_DID_BIT_SET(dep_req->pfb))
322 		size++;
323 	if (ST21NFCA_NFC_DEP_NAD_BIT_SET(dep_req->pfb))
324 		size++;
325 
326 	if (skb->len < size)
327 		return -EIO;
328 
329 	/* Receiving DEP_REQ - Decoding */
330 	switch (ST21NFCA_NFC_DEP_PFB_TYPE(dep_req->pfb)) {
331 	case ST21NFCA_NFC_DEP_PFB_I_PDU:
332 		info->dep_info.curr_nfc_dep_pni =
333 				ST21NFCA_NFC_DEP_PFB_PNI(dep_req->pfb);
334 		break;
335 	case ST21NFCA_NFC_DEP_PFB_ACK_NACK_PDU:
336 		pr_err("Received a ACK/NACK PDU\n");
337 		break;
338 	case ST21NFCA_NFC_DEP_PFB_SUPERVISOR_PDU:
339 		pr_err("Received a SUPERVISOR PDU\n");
340 		break;
341 	}
342 
343 	skb_pull(skb, size);
344 
345 	return nfc_tm_data_received(hdev->ndev, skb);
346 }
347 
348 static int st21nfca_tm_event_send_data(struct nfc_hci_dev *hdev,
349 				struct sk_buff *skb)
350 {
351 	u8 cmd0, cmd1;
352 	int r;
353 
354 	cmd0 = skb->data[1];
355 	switch (cmd0) {
356 	case ST21NFCA_NFCIP1_REQ:
357 		cmd1 = skb->data[2];
358 		switch (cmd1) {
359 		case ST21NFCA_NFCIP1_ATR_REQ:
360 			r = st21nfca_tm_recv_atr_req(hdev, skb);
361 			break;
362 		case ST21NFCA_NFCIP1_PSL_REQ:
363 			r = st21nfca_tm_recv_psl_req(hdev, skb);
364 			break;
365 		case ST21NFCA_NFCIP1_DEP_REQ:
366 			r = st21nfca_tm_recv_dep_req(hdev, skb);
367 			break;
368 		default:
369 			return 1;
370 		}
371 		break;
372 	default:
373 		return 1;
374 	}
375 	return r;
376 }
377 
378 /*
379  * Returns:
380  * <= 0: driver handled the event, skb consumed
381  *    1: driver does not handle the event, please do standard processing
382  */
383 int st21nfca_dep_event_received(struct nfc_hci_dev *hdev,
384 				u8 event, struct sk_buff *skb)
385 {
386 	int r = 0;
387 	struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
388 
389 	pr_debug("dep event: %d\n", event);
390 
391 	switch (event) {
392 	case ST21NFCA_EVT_CARD_ACTIVATED:
393 		info->dep_info.curr_nfc_dep_pni = 0;
394 		break;
395 	case ST21NFCA_EVT_CARD_DEACTIVATED:
396 		break;
397 	case ST21NFCA_EVT_FIELD_ON:
398 		break;
399 	case ST21NFCA_EVT_FIELD_OFF:
400 		break;
401 	case ST21NFCA_EVT_SEND_DATA:
402 		r = st21nfca_tm_event_send_data(hdev, skb);
403 		if (r < 0)
404 			return r;
405 		return 0;
406 	default:
407 		nfc_err(&hdev->ndev->dev, "Unexpected event on card f gate\n");
408 		return 1;
409 	}
410 	kfree_skb(skb);
411 	return r;
412 }
413 EXPORT_SYMBOL(st21nfca_dep_event_received);
414 
415 static void st21nfca_im_send_psl_req(struct nfc_hci_dev *hdev, u8 did, u8 bsi,
416 				     u8 bri, u8 lri)
417 {
418 	struct sk_buff *skb;
419 	struct st21nfca_psl_req *psl_req;
420 	struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
421 
422 	skb =
423 	    alloc_skb(sizeof(struct st21nfca_psl_req) + 1, GFP_KERNEL);
424 	if (!skb)
425 		return;
426 	skb_reserve(skb, 1);
427 
428 	skb_put(skb, sizeof(struct st21nfca_psl_req));
429 	psl_req = (struct st21nfca_psl_req *) skb->data;
430 
431 	psl_req->length = sizeof(struct st21nfca_psl_req);
432 	psl_req->cmd0 = ST21NFCA_NFCIP1_REQ;
433 	psl_req->cmd1 = ST21NFCA_NFCIP1_PSL_REQ;
434 	psl_req->did = did;
435 	psl_req->brs = (0x30 & bsi << 4) | (bri & 0x03);
436 	psl_req->fsl = lri;
437 
438 	*(u8 *)skb_push(skb, 1) = info->dep_info.to | 0x10;
439 
440 	st21nfca_im_send_pdu(info, skb);
441 }
442 
443 #define ST21NFCA_CB_TYPE_READER_F 1
444 static void st21nfca_im_recv_atr_res_cb(void *context, struct sk_buff *skb,
445 					int err)
446 {
447 	struct st21nfca_hci_info *info = context;
448 	struct st21nfca_atr_res *atr_res;
449 	int r;
450 
451 	if (err != 0)
452 		return;
453 
454 	if (!skb)
455 		return;
456 
457 	switch (info->async_cb_type) {
458 	case ST21NFCA_CB_TYPE_READER_F:
459 		skb_trim(skb, skb->len - 1);
460 		atr_res = (struct st21nfca_atr_res *)skb->data;
461 		r = nfc_set_remote_general_bytes(info->hdev->ndev,
462 				atr_res->gbi,
463 				skb->len - sizeof(struct st21nfca_atr_res));
464 		if (r < 0)
465 			return;
466 
467 		if (atr_res->to >= 0x0e)
468 			info->dep_info.to = 0x0e;
469 		else
470 			info->dep_info.to = atr_res->to + 1;
471 
472 		info->dep_info.to |= 0x10;
473 
474 		r = nfc_dep_link_is_up(info->hdev->ndev, info->dep_info.idx,
475 					NFC_COMM_PASSIVE, NFC_RF_INITIATOR);
476 		if (r < 0)
477 			return;
478 
479 		info->dep_info.curr_nfc_dep_pni = 0;
480 		if (ST21NFCA_PP2LRI(atr_res->ppi) != info->dep_info.lri)
481 			st21nfca_im_send_psl_req(info->hdev, atr_res->did,
482 						atr_res->bsi, atr_res->bri,
483 						ST21NFCA_PP2LRI(atr_res->ppi));
484 		break;
485 	default:
486 		kfree_skb(skb);
487 		break;
488 	}
489 }
490 
491 int st21nfca_im_send_atr_req(struct nfc_hci_dev *hdev, u8 *gb, size_t gb_len)
492 {
493 	struct sk_buff *skb;
494 	struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
495 	struct st21nfca_atr_req *atr_req;
496 	struct nfc_target *target;
497 	uint size;
498 
499 	info->dep_info.to = ST21NFCA_DEFAULT_TIMEOUT;
500 	size = ST21NFCA_ATR_REQ_MIN_SIZE + gb_len;
501 	if (size > ST21NFCA_ATR_REQ_MAX_SIZE) {
502 		PROTOCOL_ERR("14.6.1.1");
503 		return -EINVAL;
504 	}
505 
506 	skb =
507 	    alloc_skb(sizeof(struct st21nfca_atr_req) + gb_len + 1, GFP_KERNEL);
508 	if (!skb)
509 		return -ENOMEM;
510 
511 	skb_reserve(skb, 1);
512 
513 	skb_put(skb, sizeof(struct st21nfca_atr_req));
514 
515 	atr_req = (struct st21nfca_atr_req *)skb->data;
516 	memset(atr_req, 0, sizeof(struct st21nfca_atr_req));
517 
518 	atr_req->cmd0 = ST21NFCA_NFCIP1_REQ;
519 	atr_req->cmd1 = ST21NFCA_NFCIP1_ATR_REQ;
520 	memset(atr_req->nfcid3, 0, NFC_NFCID3_MAXSIZE);
521 	target = hdev->ndev->targets;
522 
523 	if (target->sensf_res_len > 0)
524 		memcpy(atr_req->nfcid3, target->sensf_res,
525 				target->sensf_res_len);
526 	else
527 		get_random_bytes(atr_req->nfcid3, NFC_NFCID3_MAXSIZE);
528 
529 	atr_req->did = 0x0;
530 
531 	atr_req->bsi = 0x00;
532 	atr_req->bri = 0x00;
533 	atr_req->ppi = ST21NFCA_LR_BITS_PAYLOAD_SIZE_254B;
534 	if (gb_len) {
535 		atr_req->ppi |= ST21NFCA_GB_BIT;
536 		skb_put_data(skb, gb, gb_len);
537 	}
538 	atr_req->length = sizeof(struct st21nfca_atr_req) + hdev->gb_len;
539 
540 	*(u8 *)skb_push(skb, 1) = info->dep_info.to | 0x10; /* timeout */
541 
542 	info->async_cb_type = ST21NFCA_CB_TYPE_READER_F;
543 	info->async_cb_context = info;
544 	info->async_cb = st21nfca_im_recv_atr_res_cb;
545 	info->dep_info.bri = atr_req->bri;
546 	info->dep_info.bsi = atr_req->bsi;
547 	info->dep_info.lri = ST21NFCA_PP2LRI(atr_req->ppi);
548 
549 	return nfc_hci_send_cmd_async(hdev, ST21NFCA_RF_READER_F_GATE,
550 				ST21NFCA_WR_XCHG_DATA, skb->data,
551 				skb->len, info->async_cb, info);
552 }
553 EXPORT_SYMBOL(st21nfca_im_send_atr_req);
554 
555 static void st21nfca_im_recv_dep_res_cb(void *context, struct sk_buff *skb,
556 					int err)
557 {
558 	struct st21nfca_hci_info *info = context;
559 	struct st21nfca_dep_req_res *dep_res;
560 
561 	int size;
562 
563 	if (err != 0)
564 		return;
565 
566 	if (!skb)
567 		return;
568 
569 	switch (info->async_cb_type) {
570 	case ST21NFCA_CB_TYPE_READER_F:
571 		dep_res = (struct st21nfca_dep_req_res *)skb->data;
572 
573 		size = 3;
574 		if (skb->len < size)
575 			goto exit;
576 
577 		if (ST21NFCA_NFC_DEP_DID_BIT_SET(dep_res->pfb))
578 			size++;
579 		if (ST21NFCA_NFC_DEP_NAD_BIT_SET(dep_res->pfb))
580 			size++;
581 
582 		if (skb->len < size)
583 			goto exit;
584 
585 		skb_trim(skb, skb->len - 1);
586 
587 		/* Receiving DEP_REQ - Decoding */
588 		switch (ST21NFCA_NFC_DEP_PFB_TYPE(dep_res->pfb)) {
589 		case ST21NFCA_NFC_DEP_PFB_ACK_NACK_PDU:
590 			pr_err("Received a ACK/NACK PDU\n");
591 			fallthrough;
592 		case ST21NFCA_NFC_DEP_PFB_I_PDU:
593 			info->dep_info.curr_nfc_dep_pni =
594 			    ST21NFCA_NFC_DEP_PFB_PNI(dep_res->pfb + 1);
595 			size++;
596 			skb_pull(skb, size);
597 			nfc_tm_data_received(info->hdev->ndev, skb);
598 			break;
599 		case ST21NFCA_NFC_DEP_PFB_SUPERVISOR_PDU:
600 			pr_err("Received a SUPERVISOR PDU\n");
601 			skb_pull(skb, size);
602 			*(u8 *)skb_push(skb, 1) = ST21NFCA_NFCIP1_DEP_REQ;
603 			*(u8 *)skb_push(skb, 1) = ST21NFCA_NFCIP1_REQ;
604 			*(u8 *)skb_push(skb, 1) = skb->len;
605 			*(u8 *)skb_push(skb, 1) = info->dep_info.to | 0x10;
606 
607 			st21nfca_im_send_pdu(info, skb);
608 			break;
609 		}
610 
611 		return;
612 	default:
613 		break;
614 	}
615 
616 exit:
617 	kfree_skb(skb);
618 }
619 
620 int st21nfca_im_send_dep_req(struct nfc_hci_dev *hdev, struct sk_buff *skb)
621 {
622 	struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
623 
624 	info->async_cb_type = ST21NFCA_CB_TYPE_READER_F;
625 	info->async_cb_context = info;
626 	info->async_cb = st21nfca_im_recv_dep_res_cb;
627 
628 	*(u8 *)skb_push(skb, 1) = info->dep_info.curr_nfc_dep_pni;
629 	*(u8 *)skb_push(skb, 1) = ST21NFCA_NFCIP1_DEP_REQ;
630 	*(u8 *)skb_push(skb, 1) = ST21NFCA_NFCIP1_REQ;
631 	*(u8 *)skb_push(skb, 1) = skb->len;
632 
633 	*(u8 *)skb_push(skb, 1) = info->dep_info.to | 0x10;
634 
635 	return nfc_hci_send_cmd_async(hdev, ST21NFCA_RF_READER_F_GATE,
636 				      ST21NFCA_WR_XCHG_DATA,
637 				      skb->data, skb->len,
638 				      info->async_cb, info);
639 }
640 EXPORT_SYMBOL(st21nfca_im_send_dep_req);
641 
642 void st21nfca_dep_init(struct nfc_hci_dev *hdev)
643 {
644 	struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
645 
646 	INIT_WORK(&info->dep_info.tx_work, st21nfca_tx_work);
647 	info->dep_info.curr_nfc_dep_pni = 0;
648 	info->dep_info.idx = 0;
649 	info->dep_info.to = ST21NFCA_DEFAULT_TIMEOUT;
650 }
651 EXPORT_SYMBOL(st21nfca_dep_init);
652 
653 void st21nfca_dep_deinit(struct nfc_hci_dev *hdev)
654 {
655 	struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
656 
657 	cancel_work_sync(&info->dep_info.tx_work);
658 }
659 EXPORT_SYMBOL(st21nfca_dep_deinit);
660