xref: /openbmc/linux/net/nfc/nci/core.c (revision 609e478b)
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_core.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, see <http://www.gnu.org/licenses/>.
24  *
25  */
26 
27 #define pr_fmt(fmt) KBUILD_MODNAME ": %s: " fmt, __func__
28 
29 #include <linux/module.h>
30 #include <linux/types.h>
31 #include <linux/workqueue.h>
32 #include <linux/completion.h>
33 #include <linux/export.h>
34 #include <linux/sched.h>
35 #include <linux/bitops.h>
36 #include <linux/skbuff.h>
37 
38 #include "../nfc.h"
39 #include <net/nfc/nci.h>
40 #include <net/nfc/nci_core.h>
41 #include <linux/nfc.h>
42 
43 static void nci_cmd_work(struct work_struct *work);
44 static void nci_rx_work(struct work_struct *work);
45 static void nci_tx_work(struct work_struct *work);
46 
47 /* ---- NCI requests ---- */
48 
49 void nci_req_complete(struct nci_dev *ndev, int result)
50 {
51 	if (ndev->req_status == NCI_REQ_PEND) {
52 		ndev->req_result = result;
53 		ndev->req_status = NCI_REQ_DONE;
54 		complete(&ndev->req_completion);
55 	}
56 }
57 
58 static void nci_req_cancel(struct nci_dev *ndev, int err)
59 {
60 	if (ndev->req_status == NCI_REQ_PEND) {
61 		ndev->req_result = err;
62 		ndev->req_status = NCI_REQ_CANCELED;
63 		complete(&ndev->req_completion);
64 	}
65 }
66 
67 /* Execute request and wait for completion. */
68 static int __nci_request(struct nci_dev *ndev,
69 			 void (*req)(struct nci_dev *ndev, unsigned long opt),
70 			 unsigned long opt, __u32 timeout)
71 {
72 	int rc = 0;
73 	long completion_rc;
74 
75 	ndev->req_status = NCI_REQ_PEND;
76 
77 	reinit_completion(&ndev->req_completion);
78 	req(ndev, opt);
79 	completion_rc =
80 		wait_for_completion_interruptible_timeout(&ndev->req_completion,
81 							  timeout);
82 
83 	pr_debug("wait_for_completion return %ld\n", completion_rc);
84 
85 	if (completion_rc > 0) {
86 		switch (ndev->req_status) {
87 		case NCI_REQ_DONE:
88 			rc = nci_to_errno(ndev->req_result);
89 			break;
90 
91 		case NCI_REQ_CANCELED:
92 			rc = -ndev->req_result;
93 			break;
94 
95 		default:
96 			rc = -ETIMEDOUT;
97 			break;
98 		}
99 	} else {
100 		pr_err("wait_for_completion_interruptible_timeout failed %ld\n",
101 		       completion_rc);
102 
103 		rc = ((completion_rc == 0) ? (-ETIMEDOUT) : (completion_rc));
104 	}
105 
106 	ndev->req_status = ndev->req_result = 0;
107 
108 	return rc;
109 }
110 
111 static inline int nci_request(struct nci_dev *ndev,
112 			      void (*req)(struct nci_dev *ndev,
113 					  unsigned long opt),
114 			      unsigned long opt, __u32 timeout)
115 {
116 	int rc;
117 
118 	if (!test_bit(NCI_UP, &ndev->flags))
119 		return -ENETDOWN;
120 
121 	/* Serialize all requests */
122 	mutex_lock(&ndev->req_lock);
123 	rc = __nci_request(ndev, req, opt, timeout);
124 	mutex_unlock(&ndev->req_lock);
125 
126 	return rc;
127 }
128 
129 static void nci_reset_req(struct nci_dev *ndev, unsigned long opt)
130 {
131 	struct nci_core_reset_cmd cmd;
132 
133 	cmd.reset_type = NCI_RESET_TYPE_RESET_CONFIG;
134 	nci_send_cmd(ndev, NCI_OP_CORE_RESET_CMD, 1, &cmd);
135 }
136 
137 static void nci_init_req(struct nci_dev *ndev, unsigned long opt)
138 {
139 	nci_send_cmd(ndev, NCI_OP_CORE_INIT_CMD, 0, NULL);
140 }
141 
142 static void nci_init_complete_req(struct nci_dev *ndev, unsigned long opt)
143 {
144 	struct nci_rf_disc_map_cmd cmd;
145 	struct disc_map_config *cfg = cmd.mapping_configs;
146 	__u8 *num = &cmd.num_mapping_configs;
147 	int i;
148 
149 	/* set rf mapping configurations */
150 	*num = 0;
151 
152 	/* by default mapping is set to NCI_RF_INTERFACE_FRAME */
153 	for (i = 0; i < ndev->num_supported_rf_interfaces; i++) {
154 		if (ndev->supported_rf_interfaces[i] ==
155 		    NCI_RF_INTERFACE_ISO_DEP) {
156 			cfg[*num].rf_protocol = NCI_RF_PROTOCOL_ISO_DEP;
157 			cfg[*num].mode = NCI_DISC_MAP_MODE_POLL |
158 				NCI_DISC_MAP_MODE_LISTEN;
159 			cfg[*num].rf_interface = NCI_RF_INTERFACE_ISO_DEP;
160 			(*num)++;
161 		} else if (ndev->supported_rf_interfaces[i] ==
162 			   NCI_RF_INTERFACE_NFC_DEP) {
163 			cfg[*num].rf_protocol = NCI_RF_PROTOCOL_NFC_DEP;
164 			cfg[*num].mode = NCI_DISC_MAP_MODE_POLL |
165 				NCI_DISC_MAP_MODE_LISTEN;
166 			cfg[*num].rf_interface = NCI_RF_INTERFACE_NFC_DEP;
167 			(*num)++;
168 		}
169 
170 		if (*num == NCI_MAX_NUM_MAPPING_CONFIGS)
171 			break;
172 	}
173 
174 	nci_send_cmd(ndev, NCI_OP_RF_DISCOVER_MAP_CMD,
175 		     (1 + ((*num) * sizeof(struct disc_map_config))), &cmd);
176 }
177 
178 struct nci_set_config_param {
179 	__u8	id;
180 	size_t	len;
181 	__u8	*val;
182 };
183 
184 static void nci_set_config_req(struct nci_dev *ndev, unsigned long opt)
185 {
186 	struct nci_set_config_param *param = (struct nci_set_config_param *)opt;
187 	struct nci_core_set_config_cmd cmd;
188 
189 	BUG_ON(param->len > NCI_MAX_PARAM_LEN);
190 
191 	cmd.num_params = 1;
192 	cmd.param.id = param->id;
193 	cmd.param.len = param->len;
194 	memcpy(cmd.param.val, param->val, param->len);
195 
196 	nci_send_cmd(ndev, NCI_OP_CORE_SET_CONFIG_CMD, (3 + param->len), &cmd);
197 }
198 
199 static void nci_rf_discover_req(struct nci_dev *ndev, unsigned long opt)
200 {
201 	struct nci_rf_disc_cmd cmd;
202 	__u32 protocols = opt;
203 
204 	cmd.num_disc_configs = 0;
205 
206 	if ((cmd.num_disc_configs < NCI_MAX_NUM_RF_CONFIGS) &&
207 	    (protocols & NFC_PROTO_JEWEL_MASK ||
208 	     protocols & NFC_PROTO_MIFARE_MASK ||
209 	     protocols & NFC_PROTO_ISO14443_MASK ||
210 	     protocols & NFC_PROTO_NFC_DEP_MASK)) {
211 		cmd.disc_configs[cmd.num_disc_configs].rf_tech_and_mode =
212 			NCI_NFC_A_PASSIVE_POLL_MODE;
213 		cmd.disc_configs[cmd.num_disc_configs].frequency = 1;
214 		cmd.num_disc_configs++;
215 	}
216 
217 	if ((cmd.num_disc_configs < NCI_MAX_NUM_RF_CONFIGS) &&
218 	    (protocols & NFC_PROTO_ISO14443_B_MASK)) {
219 		cmd.disc_configs[cmd.num_disc_configs].rf_tech_and_mode =
220 			NCI_NFC_B_PASSIVE_POLL_MODE;
221 		cmd.disc_configs[cmd.num_disc_configs].frequency = 1;
222 		cmd.num_disc_configs++;
223 	}
224 
225 	if ((cmd.num_disc_configs < NCI_MAX_NUM_RF_CONFIGS) &&
226 	    (protocols & NFC_PROTO_FELICA_MASK ||
227 	     protocols & NFC_PROTO_NFC_DEP_MASK)) {
228 		cmd.disc_configs[cmd.num_disc_configs].rf_tech_and_mode =
229 			NCI_NFC_F_PASSIVE_POLL_MODE;
230 		cmd.disc_configs[cmd.num_disc_configs].frequency = 1;
231 		cmd.num_disc_configs++;
232 	}
233 
234 	if ((cmd.num_disc_configs < NCI_MAX_NUM_RF_CONFIGS) &&
235 	    (protocols & NFC_PROTO_ISO15693_MASK)) {
236 		cmd.disc_configs[cmd.num_disc_configs].rf_tech_and_mode =
237 			NCI_NFC_V_PASSIVE_POLL_MODE;
238 		cmd.disc_configs[cmd.num_disc_configs].frequency = 1;
239 		cmd.num_disc_configs++;
240 	}
241 
242 	nci_send_cmd(ndev, NCI_OP_RF_DISCOVER_CMD,
243 		     (1 + (cmd.num_disc_configs * sizeof(struct disc_config))),
244 		     &cmd);
245 }
246 
247 struct nci_rf_discover_select_param {
248 	__u8	rf_discovery_id;
249 	__u8	rf_protocol;
250 };
251 
252 static void nci_rf_discover_select_req(struct nci_dev *ndev, unsigned long opt)
253 {
254 	struct nci_rf_discover_select_param *param =
255 		(struct nci_rf_discover_select_param *)opt;
256 	struct nci_rf_discover_select_cmd cmd;
257 
258 	cmd.rf_discovery_id = param->rf_discovery_id;
259 	cmd.rf_protocol = param->rf_protocol;
260 
261 	switch (cmd.rf_protocol) {
262 	case NCI_RF_PROTOCOL_ISO_DEP:
263 		cmd.rf_interface = NCI_RF_INTERFACE_ISO_DEP;
264 		break;
265 
266 	case NCI_RF_PROTOCOL_NFC_DEP:
267 		cmd.rf_interface = NCI_RF_INTERFACE_NFC_DEP;
268 		break;
269 
270 	default:
271 		cmd.rf_interface = NCI_RF_INTERFACE_FRAME;
272 		break;
273 	}
274 
275 	nci_send_cmd(ndev, NCI_OP_RF_DISCOVER_SELECT_CMD,
276 		     sizeof(struct nci_rf_discover_select_cmd), &cmd);
277 }
278 
279 static void nci_rf_deactivate_req(struct nci_dev *ndev, unsigned long opt)
280 {
281 	struct nci_rf_deactivate_cmd cmd;
282 
283 	cmd.type = NCI_DEACTIVATE_TYPE_IDLE_MODE;
284 
285 	nci_send_cmd(ndev, NCI_OP_RF_DEACTIVATE_CMD,
286 		     sizeof(struct nci_rf_deactivate_cmd), &cmd);
287 }
288 
289 static int nci_open_device(struct nci_dev *ndev)
290 {
291 	int rc = 0;
292 
293 	mutex_lock(&ndev->req_lock);
294 
295 	if (test_bit(NCI_UP, &ndev->flags)) {
296 		rc = -EALREADY;
297 		goto done;
298 	}
299 
300 	if (ndev->ops->open(ndev)) {
301 		rc = -EIO;
302 		goto done;
303 	}
304 
305 	atomic_set(&ndev->cmd_cnt, 1);
306 
307 	set_bit(NCI_INIT, &ndev->flags);
308 
309 	rc = __nci_request(ndev, nci_reset_req, 0,
310 			   msecs_to_jiffies(NCI_RESET_TIMEOUT));
311 
312 	if (ndev->ops->setup)
313 		ndev->ops->setup(ndev);
314 
315 	if (!rc) {
316 		rc = __nci_request(ndev, nci_init_req, 0,
317 				   msecs_to_jiffies(NCI_INIT_TIMEOUT));
318 	}
319 
320 	if (!rc) {
321 		rc = __nci_request(ndev, nci_init_complete_req, 0,
322 				   msecs_to_jiffies(NCI_INIT_TIMEOUT));
323 	}
324 
325 	clear_bit(NCI_INIT, &ndev->flags);
326 
327 	if (!rc) {
328 		set_bit(NCI_UP, &ndev->flags);
329 		nci_clear_target_list(ndev);
330 		atomic_set(&ndev->state, NCI_IDLE);
331 	} else {
332 		/* Init failed, cleanup */
333 		skb_queue_purge(&ndev->cmd_q);
334 		skb_queue_purge(&ndev->rx_q);
335 		skb_queue_purge(&ndev->tx_q);
336 
337 		ndev->ops->close(ndev);
338 		ndev->flags = 0;
339 	}
340 
341 done:
342 	mutex_unlock(&ndev->req_lock);
343 	return rc;
344 }
345 
346 static int nci_close_device(struct nci_dev *ndev)
347 {
348 	nci_req_cancel(ndev, ENODEV);
349 	mutex_lock(&ndev->req_lock);
350 
351 	if (!test_and_clear_bit(NCI_UP, &ndev->flags)) {
352 		del_timer_sync(&ndev->cmd_timer);
353 		del_timer_sync(&ndev->data_timer);
354 		mutex_unlock(&ndev->req_lock);
355 		return 0;
356 	}
357 
358 	/* Drop RX and TX queues */
359 	skb_queue_purge(&ndev->rx_q);
360 	skb_queue_purge(&ndev->tx_q);
361 
362 	/* Flush RX and TX wq */
363 	flush_workqueue(ndev->rx_wq);
364 	flush_workqueue(ndev->tx_wq);
365 
366 	/* Reset device */
367 	skb_queue_purge(&ndev->cmd_q);
368 	atomic_set(&ndev->cmd_cnt, 1);
369 
370 	set_bit(NCI_INIT, &ndev->flags);
371 	__nci_request(ndev, nci_reset_req, 0,
372 		      msecs_to_jiffies(NCI_RESET_TIMEOUT));
373 	clear_bit(NCI_INIT, &ndev->flags);
374 
375 	del_timer_sync(&ndev->cmd_timer);
376 
377 	/* Flush cmd wq */
378 	flush_workqueue(ndev->cmd_wq);
379 
380 	/* After this point our queues are empty
381 	 * and no works are scheduled. */
382 	ndev->ops->close(ndev);
383 
384 	/* Clear flags */
385 	ndev->flags = 0;
386 
387 	mutex_unlock(&ndev->req_lock);
388 
389 	return 0;
390 }
391 
392 /* NCI command timer function */
393 static void nci_cmd_timer(unsigned long arg)
394 {
395 	struct nci_dev *ndev = (void *) arg;
396 
397 	atomic_set(&ndev->cmd_cnt, 1);
398 	queue_work(ndev->cmd_wq, &ndev->cmd_work);
399 }
400 
401 /* NCI data exchange timer function */
402 static void nci_data_timer(unsigned long arg)
403 {
404 	struct nci_dev *ndev = (void *) arg;
405 
406 	set_bit(NCI_DATA_EXCHANGE_TO, &ndev->flags);
407 	queue_work(ndev->rx_wq, &ndev->rx_work);
408 }
409 
410 static int nci_dev_up(struct nfc_dev *nfc_dev)
411 {
412 	struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
413 
414 	return nci_open_device(ndev);
415 }
416 
417 static int nci_dev_down(struct nfc_dev *nfc_dev)
418 {
419 	struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
420 
421 	return nci_close_device(ndev);
422 }
423 
424 int nci_set_config(struct nci_dev *ndev, __u8 id, size_t len, __u8 *val)
425 {
426 	struct nci_set_config_param param;
427 
428 	if (!val || !len)
429 		return 0;
430 
431 	param.id = id;
432 	param.len = len;
433 	param.val = val;
434 
435 	return __nci_request(ndev, nci_set_config_req, (unsigned long)&param,
436 			     msecs_to_jiffies(NCI_SET_CONFIG_TIMEOUT));
437 }
438 EXPORT_SYMBOL(nci_set_config);
439 
440 static int nci_set_local_general_bytes(struct nfc_dev *nfc_dev)
441 {
442 	struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
443 	struct nci_set_config_param param;
444 
445 	param.val = nfc_get_local_general_bytes(nfc_dev, &param.len);
446 	if ((param.val == NULL) || (param.len == 0))
447 		return 0;
448 
449 	if (param.len > NFC_MAX_GT_LEN)
450 		return -EINVAL;
451 
452 	param.id = NCI_PN_ATR_REQ_GEN_BYTES;
453 
454 	return nci_request(ndev, nci_set_config_req, (unsigned long)&param,
455 			   msecs_to_jiffies(NCI_SET_CONFIG_TIMEOUT));
456 }
457 
458 static int nci_start_poll(struct nfc_dev *nfc_dev,
459 			  __u32 im_protocols, __u32 tm_protocols)
460 {
461 	struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
462 	int rc;
463 
464 	if ((atomic_read(&ndev->state) == NCI_DISCOVERY) ||
465 	    (atomic_read(&ndev->state) == NCI_W4_ALL_DISCOVERIES)) {
466 		pr_err("unable to start poll, since poll is already active\n");
467 		return -EBUSY;
468 	}
469 
470 	if (ndev->target_active_prot) {
471 		pr_err("there is an active target\n");
472 		return -EBUSY;
473 	}
474 
475 	if ((atomic_read(&ndev->state) == NCI_W4_HOST_SELECT) ||
476 	    (atomic_read(&ndev->state) == NCI_POLL_ACTIVE)) {
477 		pr_debug("target active or w4 select, implicitly deactivate\n");
478 
479 		rc = nci_request(ndev, nci_rf_deactivate_req, 0,
480 				 msecs_to_jiffies(NCI_RF_DEACTIVATE_TIMEOUT));
481 		if (rc)
482 			return -EBUSY;
483 	}
484 
485 	if (im_protocols & NFC_PROTO_NFC_DEP_MASK) {
486 		rc = nci_set_local_general_bytes(nfc_dev);
487 		if (rc) {
488 			pr_err("failed to set local general bytes\n");
489 			return rc;
490 		}
491 	}
492 
493 	rc = nci_request(ndev, nci_rf_discover_req, im_protocols,
494 			 msecs_to_jiffies(NCI_RF_DISC_TIMEOUT));
495 
496 	if (!rc)
497 		ndev->poll_prots = im_protocols;
498 
499 	return rc;
500 }
501 
502 static void nci_stop_poll(struct nfc_dev *nfc_dev)
503 {
504 	struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
505 
506 	if ((atomic_read(&ndev->state) != NCI_DISCOVERY) &&
507 	    (atomic_read(&ndev->state) != NCI_W4_ALL_DISCOVERIES)) {
508 		pr_err("unable to stop poll, since poll is not active\n");
509 		return;
510 	}
511 
512 	nci_request(ndev, nci_rf_deactivate_req, 0,
513 		    msecs_to_jiffies(NCI_RF_DEACTIVATE_TIMEOUT));
514 }
515 
516 static int nci_activate_target(struct nfc_dev *nfc_dev,
517 			       struct nfc_target *target, __u32 protocol)
518 {
519 	struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
520 	struct nci_rf_discover_select_param param;
521 	struct nfc_target *nci_target = NULL;
522 	int i;
523 	int rc = 0;
524 
525 	pr_debug("target_idx %d, protocol 0x%x\n", target->idx, protocol);
526 
527 	if ((atomic_read(&ndev->state) != NCI_W4_HOST_SELECT) &&
528 	    (atomic_read(&ndev->state) != NCI_POLL_ACTIVE)) {
529 		pr_err("there is no available target to activate\n");
530 		return -EINVAL;
531 	}
532 
533 	if (ndev->target_active_prot) {
534 		pr_err("there is already an active target\n");
535 		return -EBUSY;
536 	}
537 
538 	for (i = 0; i < ndev->n_targets; i++) {
539 		if (ndev->targets[i].idx == target->idx) {
540 			nci_target = &ndev->targets[i];
541 			break;
542 		}
543 	}
544 
545 	if (!nci_target) {
546 		pr_err("unable to find the selected target\n");
547 		return -EINVAL;
548 	}
549 
550 	if (!(nci_target->supported_protocols & (1 << protocol))) {
551 		pr_err("target does not support the requested protocol 0x%x\n",
552 		       protocol);
553 		return -EINVAL;
554 	}
555 
556 	if (atomic_read(&ndev->state) == NCI_W4_HOST_SELECT) {
557 		param.rf_discovery_id = nci_target->logical_idx;
558 
559 		if (protocol == NFC_PROTO_JEWEL)
560 			param.rf_protocol = NCI_RF_PROTOCOL_T1T;
561 		else if (protocol == NFC_PROTO_MIFARE)
562 			param.rf_protocol = NCI_RF_PROTOCOL_T2T;
563 		else if (protocol == NFC_PROTO_FELICA)
564 			param.rf_protocol = NCI_RF_PROTOCOL_T3T;
565 		else if (protocol == NFC_PROTO_ISO14443 ||
566 			 protocol == NFC_PROTO_ISO14443_B)
567 			param.rf_protocol = NCI_RF_PROTOCOL_ISO_DEP;
568 		else
569 			param.rf_protocol = NCI_RF_PROTOCOL_NFC_DEP;
570 
571 		rc = nci_request(ndev, nci_rf_discover_select_req,
572 				 (unsigned long)&param,
573 				 msecs_to_jiffies(NCI_RF_DISC_SELECT_TIMEOUT));
574 	}
575 
576 	if (!rc)
577 		ndev->target_active_prot = protocol;
578 
579 	return rc;
580 }
581 
582 static void nci_deactivate_target(struct nfc_dev *nfc_dev,
583 				  struct nfc_target *target)
584 {
585 	struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
586 
587 	pr_debug("entry\n");
588 
589 	if (!ndev->target_active_prot) {
590 		pr_err("unable to deactivate target, no active target\n");
591 		return;
592 	}
593 
594 	ndev->target_active_prot = 0;
595 
596 	if (atomic_read(&ndev->state) == NCI_POLL_ACTIVE) {
597 		nci_request(ndev, nci_rf_deactivate_req, 0,
598 			    msecs_to_jiffies(NCI_RF_DEACTIVATE_TIMEOUT));
599 	}
600 }
601 
602 static int nci_dep_link_up(struct nfc_dev *nfc_dev, struct nfc_target *target,
603 			   __u8 comm_mode, __u8 *gb, size_t gb_len)
604 {
605 	struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
606 	int rc;
607 
608 	pr_debug("target_idx %d, comm_mode %d\n", target->idx, comm_mode);
609 
610 	rc = nci_activate_target(nfc_dev, target, NFC_PROTO_NFC_DEP);
611 	if (rc)
612 		return rc;
613 
614 	rc = nfc_set_remote_general_bytes(nfc_dev, ndev->remote_gb,
615 					  ndev->remote_gb_len);
616 	if (!rc)
617 		rc = nfc_dep_link_is_up(nfc_dev, target->idx, NFC_COMM_PASSIVE,
618 					NFC_RF_INITIATOR);
619 
620 	return rc;
621 }
622 
623 static int nci_dep_link_down(struct nfc_dev *nfc_dev)
624 {
625 	pr_debug("entry\n");
626 
627 	nci_deactivate_target(nfc_dev, NULL);
628 
629 	return 0;
630 }
631 
632 
633 static int nci_transceive(struct nfc_dev *nfc_dev, struct nfc_target *target,
634 			  struct sk_buff *skb,
635 			  data_exchange_cb_t cb, void *cb_context)
636 {
637 	struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
638 	int rc;
639 
640 	pr_debug("target_idx %d, len %d\n", target->idx, skb->len);
641 
642 	if (!ndev->target_active_prot) {
643 		pr_err("unable to exchange data, no active target\n");
644 		return -EINVAL;
645 	}
646 
647 	if (test_and_set_bit(NCI_DATA_EXCHANGE, &ndev->flags))
648 		return -EBUSY;
649 
650 	/* store cb and context to be used on receiving data */
651 	ndev->data_exchange_cb = cb;
652 	ndev->data_exchange_cb_context = cb_context;
653 
654 	rc = nci_send_data(ndev, NCI_STATIC_RF_CONN_ID, skb);
655 	if (rc)
656 		clear_bit(NCI_DATA_EXCHANGE, &ndev->flags);
657 
658 	return rc;
659 }
660 
661 static int nci_enable_se(struct nfc_dev *nfc_dev, u32 se_idx)
662 {
663 	return 0;
664 }
665 
666 static int nci_disable_se(struct nfc_dev *nfc_dev, u32 se_idx)
667 {
668 	return 0;
669 }
670 
671 static int nci_discover_se(struct nfc_dev *nfc_dev)
672 {
673 	return 0;
674 }
675 
676 static struct nfc_ops nci_nfc_ops = {
677 	.dev_up = nci_dev_up,
678 	.dev_down = nci_dev_down,
679 	.start_poll = nci_start_poll,
680 	.stop_poll = nci_stop_poll,
681 	.dep_link_up = nci_dep_link_up,
682 	.dep_link_down = nci_dep_link_down,
683 	.activate_target = nci_activate_target,
684 	.deactivate_target = nci_deactivate_target,
685 	.im_transceive = nci_transceive,
686 	.enable_se = nci_enable_se,
687 	.disable_se = nci_disable_se,
688 	.discover_se = nci_discover_se,
689 };
690 
691 /* ---- Interface to NCI drivers ---- */
692 
693 /**
694  * nci_allocate_device - allocate a new nci device
695  *
696  * @ops: device operations
697  * @supported_protocols: NFC protocols supported by the device
698  */
699 struct nci_dev *nci_allocate_device(struct nci_ops *ops,
700 				    __u32 supported_protocols,
701 				    int tx_headroom, int tx_tailroom)
702 {
703 	struct nci_dev *ndev;
704 
705 	pr_debug("supported_protocols 0x%x\n", supported_protocols);
706 
707 	if (!ops->open || !ops->close || !ops->send)
708 		return NULL;
709 
710 	if (!supported_protocols)
711 		return NULL;
712 
713 	ndev = kzalloc(sizeof(struct nci_dev), GFP_KERNEL);
714 	if (!ndev)
715 		return NULL;
716 
717 	ndev->ops = ops;
718 	ndev->tx_headroom = tx_headroom;
719 	ndev->tx_tailroom = tx_tailroom;
720 	init_completion(&ndev->req_completion);
721 
722 	ndev->nfc_dev = nfc_allocate_device(&nci_nfc_ops,
723 					    supported_protocols,
724 					    tx_headroom + NCI_DATA_HDR_SIZE,
725 					    tx_tailroom);
726 	if (!ndev->nfc_dev)
727 		goto free_exit;
728 
729 	nfc_set_drvdata(ndev->nfc_dev, ndev);
730 
731 	return ndev;
732 
733 free_exit:
734 	kfree(ndev);
735 	return NULL;
736 }
737 EXPORT_SYMBOL(nci_allocate_device);
738 
739 /**
740  * nci_free_device - deallocate nci device
741  *
742  * @ndev: The nci device to deallocate
743  */
744 void nci_free_device(struct nci_dev *ndev)
745 {
746 	nfc_free_device(ndev->nfc_dev);
747 	kfree(ndev);
748 }
749 EXPORT_SYMBOL(nci_free_device);
750 
751 /**
752  * nci_register_device - register a nci device in the nfc subsystem
753  *
754  * @dev: The nci device to register
755  */
756 int nci_register_device(struct nci_dev *ndev)
757 {
758 	int rc;
759 	struct device *dev = &ndev->nfc_dev->dev;
760 	char name[32];
761 
762 	ndev->flags = 0;
763 
764 	INIT_WORK(&ndev->cmd_work, nci_cmd_work);
765 	snprintf(name, sizeof(name), "%s_nci_cmd_wq", dev_name(dev));
766 	ndev->cmd_wq = create_singlethread_workqueue(name);
767 	if (!ndev->cmd_wq) {
768 		rc = -ENOMEM;
769 		goto exit;
770 	}
771 
772 	INIT_WORK(&ndev->rx_work, nci_rx_work);
773 	snprintf(name, sizeof(name), "%s_nci_rx_wq", dev_name(dev));
774 	ndev->rx_wq = create_singlethread_workqueue(name);
775 	if (!ndev->rx_wq) {
776 		rc = -ENOMEM;
777 		goto destroy_cmd_wq_exit;
778 	}
779 
780 	INIT_WORK(&ndev->tx_work, nci_tx_work);
781 	snprintf(name, sizeof(name), "%s_nci_tx_wq", dev_name(dev));
782 	ndev->tx_wq = create_singlethread_workqueue(name);
783 	if (!ndev->tx_wq) {
784 		rc = -ENOMEM;
785 		goto destroy_rx_wq_exit;
786 	}
787 
788 	skb_queue_head_init(&ndev->cmd_q);
789 	skb_queue_head_init(&ndev->rx_q);
790 	skb_queue_head_init(&ndev->tx_q);
791 
792 	setup_timer(&ndev->cmd_timer, nci_cmd_timer,
793 		    (unsigned long) ndev);
794 	setup_timer(&ndev->data_timer, nci_data_timer,
795 		    (unsigned long) ndev);
796 
797 	mutex_init(&ndev->req_lock);
798 
799 	rc = nfc_register_device(ndev->nfc_dev);
800 	if (rc)
801 		goto destroy_rx_wq_exit;
802 
803 	goto exit;
804 
805 destroy_rx_wq_exit:
806 	destroy_workqueue(ndev->rx_wq);
807 
808 destroy_cmd_wq_exit:
809 	destroy_workqueue(ndev->cmd_wq);
810 
811 exit:
812 	return rc;
813 }
814 EXPORT_SYMBOL(nci_register_device);
815 
816 /**
817  * nci_unregister_device - unregister a nci device in the nfc subsystem
818  *
819  * @dev: The nci device to unregister
820  */
821 void nci_unregister_device(struct nci_dev *ndev)
822 {
823 	nci_close_device(ndev);
824 
825 	destroy_workqueue(ndev->cmd_wq);
826 	destroy_workqueue(ndev->rx_wq);
827 	destroy_workqueue(ndev->tx_wq);
828 
829 	nfc_unregister_device(ndev->nfc_dev);
830 }
831 EXPORT_SYMBOL(nci_unregister_device);
832 
833 /**
834  * nci_recv_frame - receive frame from NCI drivers
835  *
836  * @ndev: The nci device
837  * @skb: The sk_buff to receive
838  */
839 int nci_recv_frame(struct nci_dev *ndev, struct sk_buff *skb)
840 {
841 	pr_debug("len %d\n", skb->len);
842 
843 	if (!ndev || (!test_bit(NCI_UP, &ndev->flags) &&
844 	    !test_bit(NCI_INIT, &ndev->flags))) {
845 		kfree_skb(skb);
846 		return -ENXIO;
847 	}
848 
849 	/* Queue frame for rx worker thread */
850 	skb_queue_tail(&ndev->rx_q, skb);
851 	queue_work(ndev->rx_wq, &ndev->rx_work);
852 
853 	return 0;
854 }
855 EXPORT_SYMBOL(nci_recv_frame);
856 
857 static int nci_send_frame(struct nci_dev *ndev, struct sk_buff *skb)
858 {
859 	pr_debug("len %d\n", skb->len);
860 
861 	if (!ndev) {
862 		kfree_skb(skb);
863 		return -ENODEV;
864 	}
865 
866 	/* Get rid of skb owner, prior to sending to the driver. */
867 	skb_orphan(skb);
868 
869 	/* Send copy to sniffer */
870 	nfc_send_to_raw_sock(ndev->nfc_dev, skb,
871 			     RAW_PAYLOAD_NCI, NFC_DIRECTION_TX);
872 
873 	return ndev->ops->send(ndev, skb);
874 }
875 
876 /* Send NCI command */
877 int nci_send_cmd(struct nci_dev *ndev, __u16 opcode, __u8 plen, void *payload)
878 {
879 	struct nci_ctrl_hdr *hdr;
880 	struct sk_buff *skb;
881 
882 	pr_debug("opcode 0x%x, plen %d\n", opcode, plen);
883 
884 	skb = nci_skb_alloc(ndev, (NCI_CTRL_HDR_SIZE + plen), GFP_KERNEL);
885 	if (!skb) {
886 		pr_err("no memory for command\n");
887 		return -ENOMEM;
888 	}
889 
890 	hdr = (struct nci_ctrl_hdr *) skb_put(skb, NCI_CTRL_HDR_SIZE);
891 	hdr->gid = nci_opcode_gid(opcode);
892 	hdr->oid = nci_opcode_oid(opcode);
893 	hdr->plen = plen;
894 
895 	nci_mt_set((__u8 *)hdr, NCI_MT_CMD_PKT);
896 	nci_pbf_set((__u8 *)hdr, NCI_PBF_LAST);
897 
898 	if (plen)
899 		memcpy(skb_put(skb, plen), payload, plen);
900 
901 	skb_queue_tail(&ndev->cmd_q, skb);
902 	queue_work(ndev->cmd_wq, &ndev->cmd_work);
903 
904 	return 0;
905 }
906 
907 /* ---- NCI TX Data worker thread ---- */
908 
909 static void nci_tx_work(struct work_struct *work)
910 {
911 	struct nci_dev *ndev = container_of(work, struct nci_dev, tx_work);
912 	struct sk_buff *skb;
913 
914 	pr_debug("credits_cnt %d\n", atomic_read(&ndev->credits_cnt));
915 
916 	/* Send queued tx data */
917 	while (atomic_read(&ndev->credits_cnt)) {
918 		skb = skb_dequeue(&ndev->tx_q);
919 		if (!skb)
920 			return;
921 
922 		/* Check if data flow control is used */
923 		if (atomic_read(&ndev->credits_cnt) !=
924 		    NCI_DATA_FLOW_CONTROL_NOT_USED)
925 			atomic_dec(&ndev->credits_cnt);
926 
927 		pr_debug("NCI TX: MT=data, PBF=%d, conn_id=%d, plen=%d\n",
928 			 nci_pbf(skb->data),
929 			 nci_conn_id(skb->data),
930 			 nci_plen(skb->data));
931 
932 		nci_send_frame(ndev, skb);
933 
934 		mod_timer(&ndev->data_timer,
935 			  jiffies + msecs_to_jiffies(NCI_DATA_TIMEOUT));
936 	}
937 }
938 
939 /* ----- NCI RX worker thread (data & control) ----- */
940 
941 static void nci_rx_work(struct work_struct *work)
942 {
943 	struct nci_dev *ndev = container_of(work, struct nci_dev, rx_work);
944 	struct sk_buff *skb;
945 
946 	while ((skb = skb_dequeue(&ndev->rx_q))) {
947 
948 		/* Send copy to sniffer */
949 		nfc_send_to_raw_sock(ndev->nfc_dev, skb,
950 				     RAW_PAYLOAD_NCI, NFC_DIRECTION_RX);
951 
952 		/* Process frame */
953 		switch (nci_mt(skb->data)) {
954 		case NCI_MT_RSP_PKT:
955 			nci_rsp_packet(ndev, skb);
956 			break;
957 
958 		case NCI_MT_NTF_PKT:
959 			nci_ntf_packet(ndev, skb);
960 			break;
961 
962 		case NCI_MT_DATA_PKT:
963 			nci_rx_data_packet(ndev, skb);
964 			break;
965 
966 		default:
967 			pr_err("unknown MT 0x%x\n", nci_mt(skb->data));
968 			kfree_skb(skb);
969 			break;
970 		}
971 	}
972 
973 	/* check if a data exchange timout has occurred */
974 	if (test_bit(NCI_DATA_EXCHANGE_TO, &ndev->flags)) {
975 		/* complete the data exchange transaction, if exists */
976 		if (test_bit(NCI_DATA_EXCHANGE, &ndev->flags))
977 			nci_data_exchange_complete(ndev, NULL, -ETIMEDOUT);
978 
979 		clear_bit(NCI_DATA_EXCHANGE_TO, &ndev->flags);
980 	}
981 }
982 
983 /* ----- NCI TX CMD worker thread ----- */
984 
985 static void nci_cmd_work(struct work_struct *work)
986 {
987 	struct nci_dev *ndev = container_of(work, struct nci_dev, cmd_work);
988 	struct sk_buff *skb;
989 
990 	pr_debug("cmd_cnt %d\n", atomic_read(&ndev->cmd_cnt));
991 
992 	/* Send queued command */
993 	if (atomic_read(&ndev->cmd_cnt)) {
994 		skb = skb_dequeue(&ndev->cmd_q);
995 		if (!skb)
996 			return;
997 
998 		atomic_dec(&ndev->cmd_cnt);
999 
1000 		pr_debug("NCI TX: MT=cmd, PBF=%d, GID=0x%x, OID=0x%x, plen=%d\n",
1001 			 nci_pbf(skb->data),
1002 			 nci_opcode_gid(nci_opcode(skb->data)),
1003 			 nci_opcode_oid(nci_opcode(skb->data)),
1004 			 nci_plen(skb->data));
1005 
1006 		nci_send_frame(ndev, skb);
1007 
1008 		mod_timer(&ndev->cmd_timer,
1009 			  jiffies + msecs_to_jiffies(NCI_CMD_TIMEOUT));
1010 	}
1011 }
1012 
1013 MODULE_LICENSE("GPL");
1014