xref: /openbmc/linux/net/nfc/nci/ntf.c (revision 95e9fd10)
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 = min_t(__u8, *data++, NFC_NFCID1_MAXSIZE);
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 = min_t(__u8, *data++, NFC_SENSB_RES_MAXSIZE);
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 = min_t(__u8, *data++, NFC_SENSF_RES_MAXSIZE);
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 		if (rf_tech_and_mode == NCI_NFC_A_PASSIVE_POLL_MODE)
174 			protocol = NFC_PROTO_ISO14443_MASK;
175 		else
176 			protocol = NFC_PROTO_ISO14443_B_MASK;
177 	else if (rf_protocol == NCI_RF_PROTOCOL_T3T)
178 		protocol = NFC_PROTO_FELICA_MASK;
179 	else
180 		protocol = 0;
181 
182 	if (!(protocol & ndev->poll_prots)) {
183 		pr_err("the target found does not have the desired protocol\n");
184 		return -EPROTO;
185 	}
186 
187 	if (rf_tech_and_mode == NCI_NFC_A_PASSIVE_POLL_MODE) {
188 		nfca_poll = (struct rf_tech_specific_params_nfca_poll *)params;
189 
190 		target->sens_res = nfca_poll->sens_res;
191 		target->sel_res = nfca_poll->sel_res;
192 		target->nfcid1_len = nfca_poll->nfcid1_len;
193 		if (target->nfcid1_len > 0) {
194 			memcpy(target->nfcid1, nfca_poll->nfcid1,
195 			       target->nfcid1_len);
196 		}
197 	} else if (rf_tech_and_mode == NCI_NFC_B_PASSIVE_POLL_MODE) {
198 		nfcb_poll = (struct rf_tech_specific_params_nfcb_poll *)params;
199 
200 		target->sensb_res_len = nfcb_poll->sensb_res_len;
201 		if (target->sensb_res_len > 0) {
202 			memcpy(target->sensb_res, nfcb_poll->sensb_res,
203 			       target->sensb_res_len);
204 		}
205 	} else if (rf_tech_and_mode == NCI_NFC_F_PASSIVE_POLL_MODE) {
206 		nfcf_poll = (struct rf_tech_specific_params_nfcf_poll *)params;
207 
208 		target->sensf_res_len = nfcf_poll->sensf_res_len;
209 		if (target->sensf_res_len > 0) {
210 			memcpy(target->sensf_res, nfcf_poll->sensf_res,
211 			       target->sensf_res_len);
212 		}
213 	} else {
214 		pr_err("unsupported rf_tech_and_mode 0x%x\n", rf_tech_and_mode);
215 		return -EPROTO;
216 	}
217 
218 	target->supported_protocols |= protocol;
219 
220 	pr_debug("protocol 0x%x\n", protocol);
221 
222 	return 0;
223 }
224 
225 static void nci_add_new_target(struct nci_dev *ndev,
226 			       struct nci_rf_discover_ntf *ntf)
227 {
228 	struct nfc_target *target;
229 	int i, rc;
230 
231 	for (i = 0; i < ndev->n_targets; i++) {
232 		target = &ndev->targets[i];
233 		if (target->logical_idx == ntf->rf_discovery_id) {
234 			/* This target already exists, add the new protocol */
235 			nci_add_new_protocol(ndev, target, ntf->rf_protocol,
236 					     ntf->rf_tech_and_mode,
237 					     &ntf->rf_tech_specific_params);
238 			return;
239 		}
240 	}
241 
242 	/* This is a new target, check if we've enough room */
243 	if (ndev->n_targets == NCI_MAX_DISCOVERED_TARGETS) {
244 		pr_debug("not enough room, ignoring new target...\n");
245 		return;
246 	}
247 
248 	target = &ndev->targets[ndev->n_targets];
249 
250 	rc = nci_add_new_protocol(ndev, target, ntf->rf_protocol,
251 				  ntf->rf_tech_and_mode,
252 				  &ntf->rf_tech_specific_params);
253 	if (!rc) {
254 		target->logical_idx = ntf->rf_discovery_id;
255 		ndev->n_targets++;
256 
257 		pr_debug("logical idx %d, n_targets %d\n", target->logical_idx,
258 			 ndev->n_targets);
259 	}
260 }
261 
262 void nci_clear_target_list(struct nci_dev *ndev)
263 {
264 	memset(ndev->targets, 0,
265 	       (sizeof(struct nfc_target)*NCI_MAX_DISCOVERED_TARGETS));
266 
267 	ndev->n_targets = 0;
268 }
269 
270 static void nci_rf_discover_ntf_packet(struct nci_dev *ndev,
271 				       struct sk_buff *skb)
272 {
273 	struct nci_rf_discover_ntf ntf;
274 	__u8 *data = skb->data;
275 	bool add_target = true;
276 
277 	ntf.rf_discovery_id = *data++;
278 	ntf.rf_protocol = *data++;
279 	ntf.rf_tech_and_mode = *data++;
280 	ntf.rf_tech_specific_params_len = *data++;
281 
282 	pr_debug("rf_discovery_id %d\n", ntf.rf_discovery_id);
283 	pr_debug("rf_protocol 0x%x\n", ntf.rf_protocol);
284 	pr_debug("rf_tech_and_mode 0x%x\n", ntf.rf_tech_and_mode);
285 	pr_debug("rf_tech_specific_params_len %d\n",
286 		 ntf.rf_tech_specific_params_len);
287 
288 	if (ntf.rf_tech_specific_params_len > 0) {
289 		switch (ntf.rf_tech_and_mode) {
290 		case NCI_NFC_A_PASSIVE_POLL_MODE:
291 			data = nci_extract_rf_params_nfca_passive_poll(ndev,
292 				&(ntf.rf_tech_specific_params.nfca_poll), data);
293 			break;
294 
295 		case NCI_NFC_B_PASSIVE_POLL_MODE:
296 			data = nci_extract_rf_params_nfcb_passive_poll(ndev,
297 				&(ntf.rf_tech_specific_params.nfcb_poll), data);
298 			break;
299 
300 		case NCI_NFC_F_PASSIVE_POLL_MODE:
301 			data = nci_extract_rf_params_nfcf_passive_poll(ndev,
302 				&(ntf.rf_tech_specific_params.nfcf_poll), data);
303 			break;
304 
305 		default:
306 			pr_err("unsupported rf_tech_and_mode 0x%x\n",
307 			       ntf.rf_tech_and_mode);
308 			data += ntf.rf_tech_specific_params_len;
309 			add_target = false;
310 		}
311 	}
312 
313 	ntf.ntf_type = *data++;
314 	pr_debug("ntf_type %d\n", ntf.ntf_type);
315 
316 	if (add_target == true)
317 		nci_add_new_target(ndev, &ntf);
318 
319 	if (ntf.ntf_type == NCI_DISCOVER_NTF_TYPE_MORE) {
320 		atomic_set(&ndev->state, NCI_W4_ALL_DISCOVERIES);
321 	} else {
322 		atomic_set(&ndev->state, NCI_W4_HOST_SELECT);
323 		nfc_targets_found(ndev->nfc_dev, ndev->targets,
324 				  ndev->n_targets);
325 	}
326 }
327 
328 static int nci_extract_activation_params_iso_dep(struct nci_dev *ndev,
329 			struct nci_rf_intf_activated_ntf *ntf, __u8 *data)
330 {
331 	struct activation_params_nfca_poll_iso_dep *nfca_poll;
332 	struct activation_params_nfcb_poll_iso_dep *nfcb_poll;
333 
334 	switch (ntf->activation_rf_tech_and_mode) {
335 	case NCI_NFC_A_PASSIVE_POLL_MODE:
336 		nfca_poll = &ntf->activation_params.nfca_poll_iso_dep;
337 		nfca_poll->rats_res_len = min_t(__u8, *data++, 20);
338 		pr_debug("rats_res_len %d\n", nfca_poll->rats_res_len);
339 		if (nfca_poll->rats_res_len > 0) {
340 			memcpy(nfca_poll->rats_res,
341 			       data, nfca_poll->rats_res_len);
342 		}
343 		break;
344 
345 	case NCI_NFC_B_PASSIVE_POLL_MODE:
346 		nfcb_poll = &ntf->activation_params.nfcb_poll_iso_dep;
347 		nfcb_poll->attrib_res_len = min_t(__u8, *data++, 50);
348 		pr_debug("attrib_res_len %d\n", nfcb_poll->attrib_res_len);
349 		if (nfcb_poll->attrib_res_len > 0) {
350 			memcpy(nfcb_poll->attrib_res,
351 			       data, nfcb_poll->attrib_res_len);
352 		}
353 		break;
354 
355 	default:
356 		pr_err("unsupported activation_rf_tech_and_mode 0x%x\n",
357 		       ntf->activation_rf_tech_and_mode);
358 		return NCI_STATUS_RF_PROTOCOL_ERROR;
359 	}
360 
361 	return NCI_STATUS_OK;
362 }
363 
364 static void nci_target_auto_activated(struct nci_dev *ndev,
365 				      struct nci_rf_intf_activated_ntf *ntf)
366 {
367 	struct nfc_target *target;
368 	int rc;
369 
370 	target = &ndev->targets[ndev->n_targets];
371 
372 	rc = nci_add_new_protocol(ndev, target, ntf->rf_protocol,
373 				  ntf->activation_rf_tech_and_mode,
374 				  &ntf->rf_tech_specific_params);
375 	if (rc)
376 		return;
377 
378 	target->logical_idx = ntf->rf_discovery_id;
379 	ndev->n_targets++;
380 
381 	pr_debug("logical idx %d, n_targets %d\n",
382 		 target->logical_idx, ndev->n_targets);
383 
384 	nfc_targets_found(ndev->nfc_dev, ndev->targets, ndev->n_targets);
385 }
386 
387 static void nci_rf_intf_activated_ntf_packet(struct nci_dev *ndev,
388 					     struct sk_buff *skb)
389 {
390 	struct nci_rf_intf_activated_ntf ntf;
391 	__u8 *data = skb->data;
392 	int err = NCI_STATUS_OK;
393 
394 	ntf.rf_discovery_id = *data++;
395 	ntf.rf_interface = *data++;
396 	ntf.rf_protocol = *data++;
397 	ntf.activation_rf_tech_and_mode = *data++;
398 	ntf.max_data_pkt_payload_size = *data++;
399 	ntf.initial_num_credits = *data++;
400 	ntf.rf_tech_specific_params_len = *data++;
401 
402 	pr_debug("rf_discovery_id %d\n", ntf.rf_discovery_id);
403 	pr_debug("rf_interface 0x%x\n", ntf.rf_interface);
404 	pr_debug("rf_protocol 0x%x\n", ntf.rf_protocol);
405 	pr_debug("activation_rf_tech_and_mode 0x%x\n",
406 		 ntf.activation_rf_tech_and_mode);
407 	pr_debug("max_data_pkt_payload_size 0x%x\n",
408 		 ntf.max_data_pkt_payload_size);
409 	pr_debug("initial_num_credits 0x%x\n",
410 		 ntf.initial_num_credits);
411 	pr_debug("rf_tech_specific_params_len %d\n",
412 		 ntf.rf_tech_specific_params_len);
413 
414 	if (ntf.rf_tech_specific_params_len > 0) {
415 		switch (ntf.activation_rf_tech_and_mode) {
416 		case NCI_NFC_A_PASSIVE_POLL_MODE:
417 			data = nci_extract_rf_params_nfca_passive_poll(ndev,
418 				&(ntf.rf_tech_specific_params.nfca_poll), data);
419 			break;
420 
421 		case NCI_NFC_B_PASSIVE_POLL_MODE:
422 			data = nci_extract_rf_params_nfcb_passive_poll(ndev,
423 				&(ntf.rf_tech_specific_params.nfcb_poll), data);
424 			break;
425 
426 		case NCI_NFC_F_PASSIVE_POLL_MODE:
427 			data = nci_extract_rf_params_nfcf_passive_poll(ndev,
428 				&(ntf.rf_tech_specific_params.nfcf_poll), data);
429 			break;
430 
431 		default:
432 			pr_err("unsupported activation_rf_tech_and_mode 0x%x\n",
433 			       ntf.activation_rf_tech_and_mode);
434 			err = NCI_STATUS_RF_PROTOCOL_ERROR;
435 			goto exit;
436 		}
437 	}
438 
439 	ntf.data_exch_rf_tech_and_mode = *data++;
440 	ntf.data_exch_tx_bit_rate = *data++;
441 	ntf.data_exch_rx_bit_rate = *data++;
442 	ntf.activation_params_len = *data++;
443 
444 	pr_debug("data_exch_rf_tech_and_mode 0x%x\n",
445 		 ntf.data_exch_rf_tech_and_mode);
446 	pr_debug("data_exch_tx_bit_rate 0x%x\n", ntf.data_exch_tx_bit_rate);
447 	pr_debug("data_exch_rx_bit_rate 0x%x\n", ntf.data_exch_rx_bit_rate);
448 	pr_debug("activation_params_len %d\n", ntf.activation_params_len);
449 
450 	if (ntf.activation_params_len > 0) {
451 		switch (ntf.rf_interface) {
452 		case NCI_RF_INTERFACE_ISO_DEP:
453 			err = nci_extract_activation_params_iso_dep(ndev,
454 								    &ntf, data);
455 			break;
456 
457 		case NCI_RF_INTERFACE_FRAME:
458 			/* no activation params */
459 			break;
460 
461 		default:
462 			pr_err("unsupported rf_interface 0x%x\n",
463 			       ntf.rf_interface);
464 			err = NCI_STATUS_RF_PROTOCOL_ERROR;
465 			break;
466 		}
467 	}
468 
469 exit:
470 	if (err == NCI_STATUS_OK) {
471 		ndev->max_data_pkt_payload_size = ntf.max_data_pkt_payload_size;
472 		ndev->initial_num_credits = ntf.initial_num_credits;
473 
474 		/* set the available credits to initial value */
475 		atomic_set(&ndev->credits_cnt, ndev->initial_num_credits);
476 	}
477 
478 	if (atomic_read(&ndev->state) == NCI_DISCOVERY) {
479 		/* A single target was found and activated automatically */
480 		atomic_set(&ndev->state, NCI_POLL_ACTIVE);
481 		if (err == NCI_STATUS_OK)
482 			nci_target_auto_activated(ndev, &ntf);
483 	} else {	/* ndev->state == NCI_W4_HOST_SELECT */
484 		/* A selected target was activated, so complete the request */
485 		atomic_set(&ndev->state, NCI_POLL_ACTIVE);
486 		nci_req_complete(ndev, err);
487 	}
488 }
489 
490 static void nci_rf_deactivate_ntf_packet(struct nci_dev *ndev,
491 					 struct sk_buff *skb)
492 {
493 	struct nci_rf_deactivate_ntf *ntf = (void *) skb->data;
494 
495 	pr_debug("entry, type 0x%x, reason 0x%x\n", ntf->type, ntf->reason);
496 
497 	/* drop tx data queue */
498 	skb_queue_purge(&ndev->tx_q);
499 
500 	/* drop partial rx data packet */
501 	if (ndev->rx_data_reassembly) {
502 		kfree_skb(ndev->rx_data_reassembly);
503 		ndev->rx_data_reassembly = NULL;
504 	}
505 
506 	/* complete the data exchange transaction, if exists */
507 	if (test_bit(NCI_DATA_EXCHANGE, &ndev->flags))
508 		nci_data_exchange_complete(ndev, NULL, -EIO);
509 
510 	nci_clear_target_list(ndev);
511 	atomic_set(&ndev->state, NCI_IDLE);
512 	nci_req_complete(ndev, NCI_STATUS_OK);
513 }
514 
515 void nci_ntf_packet(struct nci_dev *ndev, struct sk_buff *skb)
516 {
517 	__u16 ntf_opcode = nci_opcode(skb->data);
518 
519 	pr_debug("NCI RX: MT=ntf, PBF=%d, GID=0x%x, OID=0x%x, plen=%d\n",
520 		 nci_pbf(skb->data),
521 		 nci_opcode_gid(ntf_opcode),
522 		 nci_opcode_oid(ntf_opcode),
523 		 nci_plen(skb->data));
524 
525 	/* strip the nci control header */
526 	skb_pull(skb, NCI_CTRL_HDR_SIZE);
527 
528 	switch (ntf_opcode) {
529 	case NCI_OP_CORE_CONN_CREDITS_NTF:
530 		nci_core_conn_credits_ntf_packet(ndev, skb);
531 		break;
532 
533 	case NCI_OP_CORE_GENERIC_ERROR_NTF:
534 		nci_core_generic_error_ntf_packet(ndev, skb);
535 		break;
536 
537 	case NCI_OP_CORE_INTF_ERROR_NTF:
538 		nci_core_conn_intf_error_ntf_packet(ndev, skb);
539 		break;
540 
541 	case NCI_OP_RF_DISCOVER_NTF:
542 		nci_rf_discover_ntf_packet(ndev, skb);
543 		break;
544 
545 	case NCI_OP_RF_INTF_ACTIVATED_NTF:
546 		nci_rf_intf_activated_ntf_packet(ndev, skb);
547 		break;
548 
549 	case NCI_OP_RF_DEACTIVATE_NTF:
550 		nci_rf_deactivate_ntf_packet(ndev, skb);
551 		break;
552 
553 	default:
554 		pr_err("unknown ntf opcode 0x%x\n", ntf_opcode);
555 		break;
556 	}
557 
558 	kfree_skb(skb);
559 }
560