xref: /openbmc/linux/net/nfc/nci/ntf.c (revision 1eb4c977)
1 /*
2  *  The NFC Controller Interface is the communication protocol between an
3  *  NFC Controller (NFCC) and a Device Host (DH).
4  *
5  *  Copyright (C) 2011 Texas Instruments, Inc.
6  *
7  *  Written by Ilan Elias <ilane@ti.com>
8  *
9  *  Acknowledgements:
10  *  This file is based on hci_event.c, which was written
11  *  by Maxim Krasnyansky.
12  *
13  *  This program is free software; you can redistribute it and/or modify
14  *  it under the terms of the GNU General Public License version 2
15  *  as published by the Free Software Foundation
16  *
17  *  This program is distributed in the hope that it will be useful,
18  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
19  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  *  GNU General Public License for more details.
21  *
22  *  You should have received a copy of the GNU General Public License
23  *  along with this program; if not, write to the Free Software
24  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
25  *
26  */
27 
28 #define pr_fmt(fmt) KBUILD_MODNAME ": %s: " fmt, __func__
29 
30 #include <linux/types.h>
31 #include <linux/interrupt.h>
32 #include <linux/bitops.h>
33 #include <linux/skbuff.h>
34 
35 #include "../nfc.h"
36 #include <net/nfc/nci.h>
37 #include <net/nfc/nci_core.h>
38 #include <linux/nfc.h>
39 
40 /* Handle NCI Notification packets */
41 
42 static void nci_core_conn_credits_ntf_packet(struct nci_dev *ndev,
43 					     struct sk_buff *skb)
44 {
45 	struct nci_core_conn_credit_ntf *ntf = (void *) skb->data;
46 	int i;
47 
48 	pr_debug("num_entries %d\n", ntf->num_entries);
49 
50 	if (ntf->num_entries > NCI_MAX_NUM_CONN)
51 		ntf->num_entries = NCI_MAX_NUM_CONN;
52 
53 	/* update the credits */
54 	for (i = 0; i < ntf->num_entries; i++) {
55 		ntf->conn_entries[i].conn_id =
56 			nci_conn_id(&ntf->conn_entries[i].conn_id);
57 
58 		pr_debug("entry[%d]: conn_id %d, credits %d\n",
59 			 i, ntf->conn_entries[i].conn_id,
60 			 ntf->conn_entries[i].credits);
61 
62 		if (ntf->conn_entries[i].conn_id == NCI_STATIC_RF_CONN_ID) {
63 			/* found static rf connection */
64 			atomic_add(ntf->conn_entries[i].credits,
65 				   &ndev->credits_cnt);
66 		}
67 	}
68 
69 	/* trigger the next tx */
70 	if (!skb_queue_empty(&ndev->tx_q))
71 		queue_work(ndev->tx_wq, &ndev->tx_work);
72 }
73 
74 static void nci_core_generic_error_ntf_packet(struct nci_dev *ndev,
75 					      struct sk_buff *skb)
76 {
77 	__u8 status = skb->data[0];
78 
79 	pr_debug("status 0x%x\n", status);
80 
81 	if (atomic_read(&ndev->state) == NCI_W4_HOST_SELECT) {
82 		/* Activation failed, so complete the request
83 		   (the state remains the same) */
84 		nci_req_complete(ndev, status);
85 	}
86 }
87 
88 static void nci_core_conn_intf_error_ntf_packet(struct nci_dev *ndev,
89 						struct sk_buff *skb)
90 {
91 	struct nci_core_intf_error_ntf *ntf = (void *) skb->data;
92 
93 	ntf->conn_id = nci_conn_id(&ntf->conn_id);
94 
95 	pr_debug("status 0x%x, conn_id %d\n", ntf->status, ntf->conn_id);
96 
97 	/* complete the data exchange transaction, if exists */
98 	if (test_bit(NCI_DATA_EXCHANGE, &ndev->flags))
99 		nci_data_exchange_complete(ndev, NULL, -EIO);
100 }
101 
102 static __u8 *nci_extract_rf_params_nfca_passive_poll(struct nci_dev *ndev,
103 			struct rf_tech_specific_params_nfca_poll *nfca_poll,
104 						     __u8 *data)
105 {
106 	nfca_poll->sens_res = __le16_to_cpu(*((__u16 *)data));
107 	data += 2;
108 
109 	nfca_poll->nfcid1_len = *data++;
110 
111 	pr_debug("sens_res 0x%x, nfcid1_len %d\n",
112 		 nfca_poll->sens_res, nfca_poll->nfcid1_len);
113 
114 	memcpy(nfca_poll->nfcid1, data, nfca_poll->nfcid1_len);
115 	data += nfca_poll->nfcid1_len;
116 
117 	nfca_poll->sel_res_len = *data++;
118 
119 	if (nfca_poll->sel_res_len != 0)
120 		nfca_poll->sel_res = *data++;
121 
122 	pr_debug("sel_res_len %d, sel_res 0x%x\n",
123 		 nfca_poll->sel_res_len,
124 		 nfca_poll->sel_res);
125 
126 	return data;
127 }
128 
129 static __u8 *nci_extract_rf_params_nfcb_passive_poll(struct nci_dev *ndev,
130 			struct rf_tech_specific_params_nfcb_poll *nfcb_poll,
131 						     __u8 *data)
132 {
133 	nfcb_poll->sensb_res_len = *data++;
134 
135 	pr_debug("sensb_res_len %d\n", nfcb_poll->sensb_res_len);
136 
137 	memcpy(nfcb_poll->sensb_res, data, nfcb_poll->sensb_res_len);
138 	data += nfcb_poll->sensb_res_len;
139 
140 	return data;
141 }
142 
143 static __u8 *nci_extract_rf_params_nfcf_passive_poll(struct nci_dev *ndev,
144 			struct rf_tech_specific_params_nfcf_poll *nfcf_poll,
145 						     __u8 *data)
146 {
147 	nfcf_poll->bit_rate = *data++;
148 	nfcf_poll->sensf_res_len = *data++;
149 
150 	pr_debug("bit_rate %d, sensf_res_len %d\n",
151 		 nfcf_poll->bit_rate, nfcf_poll->sensf_res_len);
152 
153 	memcpy(nfcf_poll->sensf_res, data, nfcf_poll->sensf_res_len);
154 	data += nfcf_poll->sensf_res_len;
155 
156 	return data;
157 }
158 
159 static int nci_add_new_protocol(struct nci_dev *ndev,
160 				struct nfc_target *target,
161 				__u8 rf_protocol,
162 				__u8 rf_tech_and_mode,
163 				void *params)
164 {
165 	struct rf_tech_specific_params_nfca_poll *nfca_poll;
166 	struct rf_tech_specific_params_nfcb_poll *nfcb_poll;
167 	struct rf_tech_specific_params_nfcf_poll *nfcf_poll;
168 	__u32 protocol;
169 
170 	if (rf_protocol == NCI_RF_PROTOCOL_T2T)
171 		protocol = NFC_PROTO_MIFARE_MASK;
172 	else if (rf_protocol == NCI_RF_PROTOCOL_ISO_DEP)
173 		protocol = NFC_PROTO_ISO14443_MASK;
174 	else if (rf_protocol == NCI_RF_PROTOCOL_T3T)
175 		protocol = NFC_PROTO_FELICA_MASK;
176 	else
177 		protocol = 0;
178 
179 	if (!(protocol & ndev->poll_prots)) {
180 		pr_err("the target found does not have the desired protocol\n");
181 		return -EPROTO;
182 	}
183 
184 	if (rf_tech_and_mode == NCI_NFC_A_PASSIVE_POLL_MODE) {
185 		nfca_poll = (struct rf_tech_specific_params_nfca_poll *)params;
186 
187 		target->sens_res = nfca_poll->sens_res;
188 		target->sel_res = nfca_poll->sel_res;
189 		target->nfcid1_len = nfca_poll->nfcid1_len;
190 		if (target->nfcid1_len > 0) {
191 			memcpy(target->nfcid1, nfca_poll->nfcid1,
192 			       target->nfcid1_len);
193 		}
194 	} else if (rf_tech_and_mode == NCI_NFC_B_PASSIVE_POLL_MODE) {
195 		nfcb_poll = (struct rf_tech_specific_params_nfcb_poll *)params;
196 
197 		target->sensb_res_len = nfcb_poll->sensb_res_len;
198 		if (target->sensb_res_len > 0) {
199 			memcpy(target->sensb_res, nfcb_poll->sensb_res,
200 			       target->sensb_res_len);
201 		}
202 	} else if (rf_tech_and_mode == NCI_NFC_F_PASSIVE_POLL_MODE) {
203 		nfcf_poll = (struct rf_tech_specific_params_nfcf_poll *)params;
204 
205 		target->sensf_res_len = nfcf_poll->sensf_res_len;
206 		if (target->sensf_res_len > 0) {
207 			memcpy(target->sensf_res, nfcf_poll->sensf_res,
208 			       target->sensf_res_len);
209 		}
210 	} else {
211 		pr_err("unsupported rf_tech_and_mode 0x%x\n", rf_tech_and_mode);
212 		return -EPROTO;
213 	}
214 
215 	target->supported_protocols |= protocol;
216 
217 	pr_debug("protocol 0x%x\n", protocol);
218 
219 	return 0;
220 }
221 
222 static void nci_add_new_target(struct nci_dev *ndev,
223 			       struct nci_rf_discover_ntf *ntf)
224 {
225 	struct nfc_target *target;
226 	int i, rc;
227 
228 	for (i = 0; i < ndev->n_targets; i++) {
229 		target = &ndev->targets[i];
230 		if (target->idx == ntf->rf_discovery_id) {
231 			/* This target already exists, add the new protocol */
232 			nci_add_new_protocol(ndev, target, ntf->rf_protocol,
233 					     ntf->rf_tech_and_mode,
234 					     &ntf->rf_tech_specific_params);
235 			return;
236 		}
237 	}
238 
239 	/* This is a new target, check if we've enough room */
240 	if (ndev->n_targets == NCI_MAX_DISCOVERED_TARGETS) {
241 		pr_debug("not enough room, ignoring new target...\n");
242 		return;
243 	}
244 
245 	target = &ndev->targets[ndev->n_targets];
246 
247 	rc = nci_add_new_protocol(ndev, target, ntf->rf_protocol,
248 				  ntf->rf_tech_and_mode,
249 				  &ntf->rf_tech_specific_params);
250 	if (!rc) {
251 		target->idx = ntf->rf_discovery_id;
252 		ndev->n_targets++;
253 
254 		pr_debug("target_idx %d, n_targets %d\n", target->idx,
255 			 ndev->n_targets);
256 	}
257 }
258 
259 void nci_clear_target_list(struct nci_dev *ndev)
260 {
261 	memset(ndev->targets, 0,
262 	       (sizeof(struct nfc_target)*NCI_MAX_DISCOVERED_TARGETS));
263 
264 	ndev->n_targets = 0;
265 }
266 
267 static void nci_rf_discover_ntf_packet(struct nci_dev *ndev,
268 				       struct sk_buff *skb)
269 {
270 	struct nci_rf_discover_ntf ntf;
271 	__u8 *data = skb->data;
272 	bool add_target = true;
273 
274 	ntf.rf_discovery_id = *data++;
275 	ntf.rf_protocol = *data++;
276 	ntf.rf_tech_and_mode = *data++;
277 	ntf.rf_tech_specific_params_len = *data++;
278 
279 	pr_debug("rf_discovery_id %d\n", ntf.rf_discovery_id);
280 	pr_debug("rf_protocol 0x%x\n", ntf.rf_protocol);
281 	pr_debug("rf_tech_and_mode 0x%x\n", ntf.rf_tech_and_mode);
282 	pr_debug("rf_tech_specific_params_len %d\n",
283 		 ntf.rf_tech_specific_params_len);
284 
285 	if (ntf.rf_tech_specific_params_len > 0) {
286 		switch (ntf.rf_tech_and_mode) {
287 		case NCI_NFC_A_PASSIVE_POLL_MODE:
288 			data = nci_extract_rf_params_nfca_passive_poll(ndev,
289 				&(ntf.rf_tech_specific_params.nfca_poll), data);
290 			break;
291 
292 		case NCI_NFC_B_PASSIVE_POLL_MODE:
293 			data = nci_extract_rf_params_nfcb_passive_poll(ndev,
294 				&(ntf.rf_tech_specific_params.nfcb_poll), data);
295 			break;
296 
297 		case NCI_NFC_F_PASSIVE_POLL_MODE:
298 			data = nci_extract_rf_params_nfcf_passive_poll(ndev,
299 				&(ntf.rf_tech_specific_params.nfcf_poll), data);
300 			break;
301 
302 		default:
303 			pr_err("unsupported rf_tech_and_mode 0x%x\n",
304 			       ntf.rf_tech_and_mode);
305 			data += ntf.rf_tech_specific_params_len;
306 			add_target = false;
307 		}
308 	}
309 
310 	ntf.ntf_type = *data++;
311 	pr_debug("ntf_type %d\n", ntf.ntf_type);
312 
313 	if (add_target == true)
314 		nci_add_new_target(ndev, &ntf);
315 
316 	if (ntf.ntf_type == NCI_DISCOVER_NTF_TYPE_MORE) {
317 		atomic_set(&ndev->state, NCI_W4_ALL_DISCOVERIES);
318 	} else {
319 		atomic_set(&ndev->state, NCI_W4_HOST_SELECT);
320 		nfc_targets_found(ndev->nfc_dev, ndev->targets,
321 				  ndev->n_targets);
322 	}
323 }
324 
325 static int nci_extract_activation_params_iso_dep(struct nci_dev *ndev,
326 			struct nci_rf_intf_activated_ntf *ntf, __u8 *data)
327 {
328 	struct activation_params_nfca_poll_iso_dep *nfca_poll;
329 	struct activation_params_nfcb_poll_iso_dep *nfcb_poll;
330 
331 	switch (ntf->activation_rf_tech_and_mode) {
332 	case NCI_NFC_A_PASSIVE_POLL_MODE:
333 		nfca_poll = &ntf->activation_params.nfca_poll_iso_dep;
334 		nfca_poll->rats_res_len = *data++;
335 		pr_debug("rats_res_len %d\n", nfca_poll->rats_res_len);
336 		if (nfca_poll->rats_res_len > 0) {
337 			memcpy(nfca_poll->rats_res,
338 			       data, nfca_poll->rats_res_len);
339 		}
340 		break;
341 
342 	case NCI_NFC_B_PASSIVE_POLL_MODE:
343 		nfcb_poll = &ntf->activation_params.nfcb_poll_iso_dep;
344 		nfcb_poll->attrib_res_len = *data++;
345 		pr_debug("attrib_res_len %d\n", nfcb_poll->attrib_res_len);
346 		if (nfcb_poll->attrib_res_len > 0) {
347 			memcpy(nfcb_poll->attrib_res,
348 			       data, nfcb_poll->attrib_res_len);
349 		}
350 		break;
351 
352 	default:
353 		pr_err("unsupported activation_rf_tech_and_mode 0x%x\n",
354 		       ntf->activation_rf_tech_and_mode);
355 		return NCI_STATUS_RF_PROTOCOL_ERROR;
356 	}
357 
358 	return NCI_STATUS_OK;
359 }
360 
361 static void nci_target_auto_activated(struct nci_dev *ndev,
362 				      struct nci_rf_intf_activated_ntf *ntf)
363 {
364 	struct nfc_target *target;
365 	int rc;
366 
367 	target = &ndev->targets[ndev->n_targets];
368 
369 	rc = nci_add_new_protocol(ndev, target, ntf->rf_protocol,
370 				  ntf->activation_rf_tech_and_mode,
371 				  &ntf->rf_tech_specific_params);
372 	if (rc)
373 		return;
374 
375 	target->idx = ntf->rf_discovery_id;
376 	ndev->n_targets++;
377 
378 	pr_debug("target_idx %d, n_targets %d\n", target->idx, ndev->n_targets);
379 
380 	nfc_targets_found(ndev->nfc_dev, ndev->targets, ndev->n_targets);
381 }
382 
383 static void nci_rf_intf_activated_ntf_packet(struct nci_dev *ndev,
384 					     struct sk_buff *skb)
385 {
386 	struct nci_rf_intf_activated_ntf ntf;
387 	__u8 *data = skb->data;
388 	int err = NCI_STATUS_OK;
389 
390 	ntf.rf_discovery_id = *data++;
391 	ntf.rf_interface = *data++;
392 	ntf.rf_protocol = *data++;
393 	ntf.activation_rf_tech_and_mode = *data++;
394 	ntf.max_data_pkt_payload_size = *data++;
395 	ntf.initial_num_credits = *data++;
396 	ntf.rf_tech_specific_params_len = *data++;
397 
398 	pr_debug("rf_discovery_id %d\n", ntf.rf_discovery_id);
399 	pr_debug("rf_interface 0x%x\n", ntf.rf_interface);
400 	pr_debug("rf_protocol 0x%x\n", ntf.rf_protocol);
401 	pr_debug("activation_rf_tech_and_mode 0x%x\n",
402 		 ntf.activation_rf_tech_and_mode);
403 	pr_debug("max_data_pkt_payload_size 0x%x\n",
404 		 ntf.max_data_pkt_payload_size);
405 	pr_debug("initial_num_credits 0x%x\n",
406 		 ntf.initial_num_credits);
407 	pr_debug("rf_tech_specific_params_len %d\n",
408 		 ntf.rf_tech_specific_params_len);
409 
410 	if (ntf.rf_tech_specific_params_len > 0) {
411 		switch (ntf.activation_rf_tech_and_mode) {
412 		case NCI_NFC_A_PASSIVE_POLL_MODE:
413 			data = nci_extract_rf_params_nfca_passive_poll(ndev,
414 				&(ntf.rf_tech_specific_params.nfca_poll), data);
415 			break;
416 
417 		case NCI_NFC_B_PASSIVE_POLL_MODE:
418 			data = nci_extract_rf_params_nfcb_passive_poll(ndev,
419 				&(ntf.rf_tech_specific_params.nfcb_poll), data);
420 			break;
421 
422 		case NCI_NFC_F_PASSIVE_POLL_MODE:
423 			data = nci_extract_rf_params_nfcf_passive_poll(ndev,
424 				&(ntf.rf_tech_specific_params.nfcf_poll), data);
425 			break;
426 
427 		default:
428 			pr_err("unsupported activation_rf_tech_and_mode 0x%x\n",
429 			       ntf.activation_rf_tech_and_mode);
430 			err = NCI_STATUS_RF_PROTOCOL_ERROR;
431 			goto exit;
432 		}
433 	}
434 
435 	ntf.data_exch_rf_tech_and_mode = *data++;
436 	ntf.data_exch_tx_bit_rate = *data++;
437 	ntf.data_exch_rx_bit_rate = *data++;
438 	ntf.activation_params_len = *data++;
439 
440 	pr_debug("data_exch_rf_tech_and_mode 0x%x\n",
441 		 ntf.data_exch_rf_tech_and_mode);
442 	pr_debug("data_exch_tx_bit_rate 0x%x\n", ntf.data_exch_tx_bit_rate);
443 	pr_debug("data_exch_rx_bit_rate 0x%x\n", ntf.data_exch_rx_bit_rate);
444 	pr_debug("activation_params_len %d\n", ntf.activation_params_len);
445 
446 	if (ntf.activation_params_len > 0) {
447 		switch (ntf.rf_interface) {
448 		case NCI_RF_INTERFACE_ISO_DEP:
449 			err = nci_extract_activation_params_iso_dep(ndev,
450 								    &ntf, data);
451 			break;
452 
453 		case NCI_RF_INTERFACE_FRAME:
454 			/* no activation params */
455 			break;
456 
457 		default:
458 			pr_err("unsupported rf_interface 0x%x\n",
459 			       ntf.rf_interface);
460 			err = NCI_STATUS_RF_PROTOCOL_ERROR;
461 			break;
462 		}
463 	}
464 
465 exit:
466 	if (err == NCI_STATUS_OK) {
467 		ndev->max_data_pkt_payload_size = ntf.max_data_pkt_payload_size;
468 		ndev->initial_num_credits = ntf.initial_num_credits;
469 
470 		/* set the available credits to initial value */
471 		atomic_set(&ndev->credits_cnt, ndev->initial_num_credits);
472 	}
473 
474 	if (atomic_read(&ndev->state) == NCI_DISCOVERY) {
475 		/* A single target was found and activated automatically */
476 		atomic_set(&ndev->state, NCI_POLL_ACTIVE);
477 		if (err == NCI_STATUS_OK)
478 			nci_target_auto_activated(ndev, &ntf);
479 	} else {	/* ndev->state == NCI_W4_HOST_SELECT */
480 		/* A selected target was activated, so complete the request */
481 		atomic_set(&ndev->state, NCI_POLL_ACTIVE);
482 		nci_req_complete(ndev, err);
483 	}
484 }
485 
486 static void nci_rf_deactivate_ntf_packet(struct nci_dev *ndev,
487 					 struct sk_buff *skb)
488 {
489 	struct nci_rf_deactivate_ntf *ntf = (void *) skb->data;
490 
491 	pr_debug("entry, type 0x%x, reason 0x%x\n", ntf->type, ntf->reason);
492 
493 	/* drop tx data queue */
494 	skb_queue_purge(&ndev->tx_q);
495 
496 	/* drop partial rx data packet */
497 	if (ndev->rx_data_reassembly) {
498 		kfree_skb(ndev->rx_data_reassembly);
499 		ndev->rx_data_reassembly = 0;
500 	}
501 
502 	/* complete the data exchange transaction, if exists */
503 	if (test_bit(NCI_DATA_EXCHANGE, &ndev->flags))
504 		nci_data_exchange_complete(ndev, NULL, -EIO);
505 
506 	nci_clear_target_list(ndev);
507 	atomic_set(&ndev->state, NCI_IDLE);
508 	nci_req_complete(ndev, NCI_STATUS_OK);
509 }
510 
511 void nci_ntf_packet(struct nci_dev *ndev, struct sk_buff *skb)
512 {
513 	__u16 ntf_opcode = nci_opcode(skb->data);
514 
515 	pr_debug("NCI RX: MT=ntf, PBF=%d, GID=0x%x, OID=0x%x, plen=%d\n",
516 		 nci_pbf(skb->data),
517 		 nci_opcode_gid(ntf_opcode),
518 		 nci_opcode_oid(ntf_opcode),
519 		 nci_plen(skb->data));
520 
521 	/* strip the nci control header */
522 	skb_pull(skb, NCI_CTRL_HDR_SIZE);
523 
524 	switch (ntf_opcode) {
525 	case NCI_OP_CORE_CONN_CREDITS_NTF:
526 		nci_core_conn_credits_ntf_packet(ndev, skb);
527 		break;
528 
529 	case NCI_OP_CORE_GENERIC_ERROR_NTF:
530 		nci_core_generic_error_ntf_packet(ndev, skb);
531 		break;
532 
533 	case NCI_OP_CORE_INTF_ERROR_NTF:
534 		nci_core_conn_intf_error_ntf_packet(ndev, skb);
535 		break;
536 
537 	case NCI_OP_RF_DISCOVER_NTF:
538 		nci_rf_discover_ntf_packet(ndev, skb);
539 		break;
540 
541 	case NCI_OP_RF_INTF_ACTIVATED_NTF:
542 		nci_rf_intf_activated_ntf_packet(ndev, skb);
543 		break;
544 
545 	case NCI_OP_RF_DEACTIVATE_NTF:
546 		nci_rf_deactivate_ntf_packet(ndev, skb);
547 		break;
548 
549 	default:
550 		pr_err("unknown ntf opcode 0x%x\n", ntf_opcode);
551 		break;
552 	}
553 
554 	kfree_skb(skb);
555 }
556