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1/*
2 * Copyright (C) 2011 Instituto Nokia de Tecnologia
3 *
4 * Authors:
5 * Lauro Ramos Venancio <lauro.venancio@openbossa.org>
6 * Aloisio Almeida Jr <aloisio.almeida@openbossa.org>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the
20 * Free Software Foundation, Inc.,
21 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
22 */
23
24#define pr_fmt(fmt) KBUILD_MODNAME ": %s: " fmt, __func__
25
26#include <linux/init.h>
27#include <linux/kernel.h>
28#include <linux/module.h>
29#include <linux/slab.h>
30#include <linux/nfc.h>
31
32#include "nfc.h"
33
34#define VERSION "0.1"
35
36#define NFC_CHECK_PRES_FREQ_MS 2000
37
38int nfc_devlist_generation;
39DEFINE_MUTEX(nfc_devlist_mutex);
40
41/**
42 * nfc_dev_up - turn on the NFC device
43 *
44 * @dev: The nfc device to be turned on
45 *
46 * The device remains up until the nfc_dev_down function is called.
47 */
48int nfc_dev_up(struct nfc_dev *dev)
49{
50 int rc = 0;
51
52 pr_debug("dev_name=%s\n", dev_name(&dev->dev));
53
54 device_lock(&dev->dev);
55
56 if (!device_is_registered(&dev->dev)) {
57 rc = -ENODEV;
58 goto error;
59 }
60
61 if (dev->dev_up) {
62 rc = -EALREADY;
63 goto error;
64 }
65
66 if (dev->ops->dev_up)
67 rc = dev->ops->dev_up(dev);
68
69 if (!rc)
70 dev->dev_up = true;
71
72error:
73 device_unlock(&dev->dev);
74 return rc;
75}
76
77/**
78 * nfc_dev_down - turn off the NFC device
79 *
80 * @dev: The nfc device to be turned off
81 */
82int nfc_dev_down(struct nfc_dev *dev)
83{
84 int rc = 0;
85
86 pr_debug("dev_name=%s\n", dev_name(&dev->dev));
87
88 device_lock(&dev->dev);
89
90 if (!device_is_registered(&dev->dev)) {
91 rc = -ENODEV;
92 goto error;
93 }
94
95 if (!dev->dev_up) {
96 rc = -EALREADY;
97 goto error;
98 }
99
100 if (dev->polling || dev->active_target) {
101 rc = -EBUSY;
102 goto error;
103 }
104
105 if (dev->ops->dev_down)
106 dev->ops->dev_down(dev);
107
108 dev->dev_up = false;
109
110error:
111 device_unlock(&dev->dev);
112 return rc;
113}
114
115/**
116 * nfc_start_poll - start polling for nfc targets
117 *
118 * @dev: The nfc device that must start polling
119 * @protocols: bitset of nfc protocols that must be used for polling
120 *
121 * The device remains polling for targets until a target is found or
122 * the nfc_stop_poll function is called.
123 */
124int nfc_start_poll(struct nfc_dev *dev, u32 protocols)
125{
126 int rc;
127
128 pr_debug("dev_name=%s protocols=0x%x\n",
129 dev_name(&dev->dev), protocols);
130
131 if (!protocols)
132 return -EINVAL;
133
134 device_lock(&dev->dev);
135
136 if (!device_is_registered(&dev->dev)) {
137 rc = -ENODEV;
138 goto error;
139 }
140
141 if (dev->polling) {
142 rc = -EBUSY;
143 goto error;
144 }
145
146 rc = dev->ops->start_poll(dev, protocols);
147 if (!rc)
148 dev->polling = true;
149
150error:
151 device_unlock(&dev->dev);
152 return rc;
153}
154
155/**
156 * nfc_stop_poll - stop polling for nfc targets
157 *
158 * @dev: The nfc device that must stop polling
159 */
160int nfc_stop_poll(struct nfc_dev *dev)
161{
162 int rc = 0;
163
164 pr_debug("dev_name=%s\n", dev_name(&dev->dev));
165
166 device_lock(&dev->dev);
167
168 if (!device_is_registered(&dev->dev)) {
169 rc = -ENODEV;
170 goto error;
171 }
172
173 if (!dev->polling) {
174 rc = -EINVAL;
175 goto error;
176 }
177
178 dev->ops->stop_poll(dev);
179 dev->polling = false;
180
181error:
182 device_unlock(&dev->dev);
183 return rc;
184}
185
186static struct nfc_target *nfc_find_target(struct nfc_dev *dev, u32 target_idx)
187{
188 int i;
189
190 if (dev->n_targets == 0)
191 return NULL;
192
193 for (i = 0; i < dev->n_targets ; i++) {
194 if (dev->targets[i].idx == target_idx)
195 return &dev->targets[i];
196 }
197
198 return NULL;
199}
200
201int nfc_dep_link_up(struct nfc_dev *dev, int target_index, u8 comm_mode)
202{
203 int rc = 0;
204 u8 *gb;
205 size_t gb_len;
206 struct nfc_target *target;
207
208 pr_debug("dev_name=%s comm %d\n", dev_name(&dev->dev), comm_mode);
209
210 if (!dev->ops->dep_link_up)
211 return -EOPNOTSUPP;
212
213 device_lock(&dev->dev);
214
215 if (!device_is_registered(&dev->dev)) {
216 rc = -ENODEV;
217 goto error;
218 }
219
220 if (dev->dep_link_up == true) {
221 rc = -EALREADY;
222 goto error;
223 }
224
225 gb = nfc_llcp_general_bytes(dev, &gb_len);
226 if (gb_len > NFC_MAX_GT_LEN) {
227 rc = -EINVAL;
228 goto error;
229 }
230
231 target = nfc_find_target(dev, target_index);
232 if (target == NULL) {
233 rc = -ENOTCONN;
234 goto error;
235 }
236
237 rc = dev->ops->dep_link_up(dev, target, comm_mode, gb, gb_len);
238 if (!rc)
239 dev->active_target = target;
240
241error:
242 device_unlock(&dev->dev);
243 return rc;
244}
245
246int nfc_dep_link_down(struct nfc_dev *dev)
247{
248 int rc = 0;
249
250 pr_debug("dev_name=%s\n", dev_name(&dev->dev));
251
252 if (!dev->ops->dep_link_down)
253 return -EOPNOTSUPP;
254
255 device_lock(&dev->dev);
256
257 if (!device_is_registered(&dev->dev)) {
258 rc = -ENODEV;
259 goto error;
260 }
261
262 if (dev->dep_link_up == false) {
263 rc = -EALREADY;
264 goto error;
265 }
266
267 if (dev->dep_rf_mode == NFC_RF_TARGET) {
268 rc = -EOPNOTSUPP;
269 goto error;
270 }
271
272 rc = dev->ops->dep_link_down(dev);
273 if (!rc) {
274 dev->dep_link_up = false;
275 dev->active_target = NULL;
276 nfc_llcp_mac_is_down(dev);
277 nfc_genl_dep_link_down_event(dev);
278 }
279
280error:
281 device_unlock(&dev->dev);
282 return rc;
283}
284
285int nfc_dep_link_is_up(struct nfc_dev *dev, u32 target_idx,
286 u8 comm_mode, u8 rf_mode)
287{
288 dev->dep_link_up = true;
289 dev->dep_rf_mode = rf_mode;
290
291 nfc_llcp_mac_is_up(dev, target_idx, comm_mode, rf_mode);
292
293 return nfc_genl_dep_link_up_event(dev, target_idx, comm_mode, rf_mode);
294}
295EXPORT_SYMBOL(nfc_dep_link_is_up);
296
297/**
298 * nfc_activate_target - prepare the target for data exchange
299 *
300 * @dev: The nfc device that found the target
301 * @target_idx: index of the target that must be activated
302 * @protocol: nfc protocol that will be used for data exchange
303 */
304int nfc_activate_target(struct nfc_dev *dev, u32 target_idx, u32 protocol)
305{
306 int rc;
307 struct nfc_target *target;
308
309 pr_debug("dev_name=%s target_idx=%u protocol=%u\n",
310 dev_name(&dev->dev), target_idx, protocol);
311
312 device_lock(&dev->dev);
313
314 if (!device_is_registered(&dev->dev)) {
315 rc = -ENODEV;
316 goto error;
317 }
318
319 if (dev->active_target) {
320 rc = -EBUSY;
321 goto error;
322 }
323
324 target = nfc_find_target(dev, target_idx);
325 if (target == NULL) {
326 rc = -ENOTCONN;
327 goto error;
328 }
329
330 rc = dev->ops->activate_target(dev, target, protocol);
331 if (!rc) {
332 dev->active_target = target;
333
334 if (dev->ops->check_presence)
335 mod_timer(&dev->check_pres_timer, jiffies +
336 msecs_to_jiffies(NFC_CHECK_PRES_FREQ_MS));
337 }
338
339error:
340 device_unlock(&dev->dev);
341 return rc;
342}
343
344/**
345 * nfc_deactivate_target - deactivate a nfc target
346 *
347 * @dev: The nfc device that found the target
348 * @target_idx: index of the target that must be deactivated
349 */
350int nfc_deactivate_target(struct nfc_dev *dev, u32 target_idx)
351{
352 int rc = 0;
353
354 pr_debug("dev_name=%s target_idx=%u\n",
355 dev_name(&dev->dev), target_idx);
356
357 device_lock(&dev->dev);
358
359 if (!device_is_registered(&dev->dev)) {
360 rc = -ENODEV;
361 goto error;
362 }
363
364 if (dev->active_target == NULL) {
365 rc = -ENOTCONN;
366 goto error;
367 }
368
369 if (dev->active_target->idx != target_idx) {
370 rc = -ENOTCONN;
371 goto error;
372 }
373
374 if (dev->ops->check_presence)
375 del_timer_sync(&dev->check_pres_timer);
376
377 dev->ops->deactivate_target(dev, dev->active_target);
378 dev->active_target = NULL;
379
380error:
381 device_unlock(&dev->dev);
382 return rc;
383}
384
385/**
386 * nfc_data_exchange - transceive data
387 *
388 * @dev: The nfc device that found the target
389 * @target_idx: index of the target
390 * @skb: data to be sent
391 * @cb: callback called when the response is received
392 * @cb_context: parameter for the callback function
393 *
394 * The user must wait for the callback before calling this function again.
395 */
396int nfc_data_exchange(struct nfc_dev *dev, u32 target_idx, struct sk_buff *skb,
397 data_exchange_cb_t cb, void *cb_context)
398{
399 int rc;
400
401 pr_debug("dev_name=%s target_idx=%u skb->len=%u\n",
402 dev_name(&dev->dev), target_idx, skb->len);
403
404 device_lock(&dev->dev);
405
406 if (!device_is_registered(&dev->dev)) {
407 rc = -ENODEV;
408 kfree_skb(skb);
409 goto error;
410 }
411
412 if (dev->active_target == NULL) {
413 rc = -ENOTCONN;
414 kfree_skb(skb);
415 goto error;
416 }
417
418 if (dev->active_target->idx != target_idx) {
419 rc = -EADDRNOTAVAIL;
420 kfree_skb(skb);
421 goto error;
422 }
423
424 if (dev->ops->check_presence)
425 del_timer_sync(&dev->check_pres_timer);
426
427 rc = dev->ops->data_exchange(dev, dev->active_target, skb, cb,
428 cb_context);
429
430 if (!rc && dev->ops->check_presence)
431 mod_timer(&dev->check_pres_timer, jiffies +
432 msecs_to_jiffies(NFC_CHECK_PRES_FREQ_MS));
433
434error:
435 device_unlock(&dev->dev);
436 return rc;
437}
438
439int nfc_set_remote_general_bytes(struct nfc_dev *dev, u8 *gb, u8 gb_len)
440{
441 pr_debug("dev_name=%s gb_len=%d\n", dev_name(&dev->dev), gb_len);
442
443 if (gb_len > NFC_MAX_GT_LEN)
444 return -EINVAL;
445
446 return nfc_llcp_set_remote_gb(dev, gb, gb_len);
447}
448EXPORT_SYMBOL(nfc_set_remote_general_bytes);
449
450/**
451 * nfc_alloc_send_skb - allocate a skb for data exchange responses
452 *
453 * @size: size to allocate
454 * @gfp: gfp flags
455 */
456struct sk_buff *nfc_alloc_send_skb(struct nfc_dev *dev, struct sock *sk,
457 unsigned int flags, unsigned int size,
458 unsigned int *err)
459{
460 struct sk_buff *skb;
461 unsigned int total_size;
462
463 total_size = size +
464 dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
465
466 skb = sock_alloc_send_skb(sk, total_size, flags & MSG_DONTWAIT, err);
467 if (skb)
468 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
469
470 return skb;
471}
472
473/**
474 * nfc_alloc_recv_skb - allocate a skb for data exchange responses
475 *
476 * @size: size to allocate
477 * @gfp: gfp flags
478 */
479struct sk_buff *nfc_alloc_recv_skb(unsigned int size, gfp_t gfp)
480{
481 struct sk_buff *skb;
482 unsigned int total_size;
483
484 total_size = size + 1;
485 skb = alloc_skb(total_size, gfp);
486
487 if (skb)
488 skb_reserve(skb, 1);
489
490 return skb;
491}
492EXPORT_SYMBOL(nfc_alloc_recv_skb);
493
494/**
495 * nfc_targets_found - inform that targets were found
496 *
497 * @dev: The nfc device that found the targets
498 * @targets: array of nfc targets found
499 * @ntargets: targets array size
500 *
501 * The device driver must call this function when one or many nfc targets
502 * are found. After calling this function, the device driver must stop
503 * polling for targets.
504 * IMPORTANT: this function must not be called from an atomic context.
505 * In addition, it must also not be called from a context that would prevent
506 * the NFC Core to call other nfc ops entry point concurrently.
507 */
508int nfc_targets_found(struct nfc_dev *dev,
509 struct nfc_target *targets, int n_targets)
510{
511 int i;
512
513 pr_debug("dev_name=%s n_targets=%d\n", dev_name(&dev->dev), n_targets);
514
515 dev->polling = false;
516
517 for (i = 0; i < n_targets; i++)
518 targets[i].idx = dev->target_next_idx++;
519
520 device_lock(&dev->dev);
521
522 dev->targets_generation++;
523
524 kfree(dev->targets);
525 dev->targets = kmemdup(targets, n_targets * sizeof(struct nfc_target),
526 GFP_ATOMIC);
527
528 if (!dev->targets) {
529 dev->n_targets = 0;
530 device_unlock(&dev->dev);
531 return -ENOMEM;
532 }
533
534 dev->n_targets = n_targets;
535 device_unlock(&dev->dev);
536
537 nfc_genl_targets_found(dev);
538
539 return 0;
540}
541EXPORT_SYMBOL(nfc_targets_found);
542
543/**
544 * nfc_target_lost - inform that an activated target went out of field
545 *
546 * @dev: The nfc device that had the activated target in field
547 * @target_idx: the nfc index of the target
548 *
549 * The device driver must call this function when the activated target
550 * goes out of the field.
551 * IMPORTANT: this function must not be called from an atomic context.
552 * In addition, it must also not be called from a context that would prevent
553 * the NFC Core to call other nfc ops entry point concurrently.
554 */
555int nfc_target_lost(struct nfc_dev *dev, u32 target_idx)
556{
557 struct nfc_target *tg;
558 int i;
559
560 pr_debug("dev_name %s n_target %d\n", dev_name(&dev->dev), target_idx);
561
562 device_lock(&dev->dev);
563
564 for (i = 0; i < dev->n_targets; i++) {
565 tg = &dev->targets[i];
566 if (tg->idx == target_idx)
567 break;
568 }
569
570 if (i == dev->n_targets) {
571 device_unlock(&dev->dev);
572 return -EINVAL;
573 }
574
575 dev->targets_generation++;
576 dev->n_targets--;
577 dev->active_target = NULL;
578
579 if (dev->n_targets) {
580 memcpy(&dev->targets[i], &dev->targets[i + 1],
581 (dev->n_targets - i) * sizeof(struct nfc_target));
582 } else {
583 kfree(dev->targets);
584 dev->targets = NULL;
585 }
586
587 device_unlock(&dev->dev);
588
589 nfc_genl_target_lost(dev, target_idx);
590
591 return 0;
592}
593EXPORT_SYMBOL(nfc_target_lost);
594
595static void nfc_release(struct device *d)
596{
597 struct nfc_dev *dev = to_nfc_dev(d);
598
599 pr_debug("dev_name=%s\n", dev_name(&dev->dev));
600
601 if (dev->ops->check_presence) {
602 del_timer_sync(&dev->check_pres_timer);
603 destroy_workqueue(dev->check_pres_wq);
604 }
605
606 nfc_genl_data_exit(&dev->genl_data);
607 kfree(dev->targets);
608 kfree(dev);
609}
610
611static void nfc_check_pres_work(struct work_struct *work)
612{
613 struct nfc_dev *dev = container_of(work, struct nfc_dev,
614 check_pres_work);
615 int rc;
616
617 device_lock(&dev->dev);
618
619 if (dev->active_target && timer_pending(&dev->check_pres_timer) == 0) {
620 rc = dev->ops->check_presence(dev, dev->active_target);
621 if (!rc) {
622 mod_timer(&dev->check_pres_timer, jiffies +
623 msecs_to_jiffies(NFC_CHECK_PRES_FREQ_MS));
624 } else {
625 u32 active_target_idx = dev->active_target->idx;
626 device_unlock(&dev->dev);
627 nfc_target_lost(dev, active_target_idx);
628 return;
629 }
630 }
631
632 device_unlock(&dev->dev);
633}
634
635static void nfc_check_pres_timeout(unsigned long data)
636{
637 struct nfc_dev *dev = (struct nfc_dev *)data;
638
639 queue_work(dev->check_pres_wq, &dev->check_pres_work);
640}
641
642struct class nfc_class = {
643 .name = "nfc",
644 .dev_release = nfc_release,
645};
646EXPORT_SYMBOL(nfc_class);
647
648static int match_idx(struct device *d, void *data)
649{
650 struct nfc_dev *dev = to_nfc_dev(d);
651 unsigned int *idx = data;
652
653 return dev->idx == *idx;
654}
655
656struct nfc_dev *nfc_get_device(unsigned int idx)
657{
658 struct device *d;
659
660 d = class_find_device(&nfc_class, NULL, &idx, match_idx);
661 if (!d)
662 return NULL;
663
664 return to_nfc_dev(d);
665}
666
667/**
668 * nfc_allocate_device - allocate a new nfc device
669 *
670 * @ops: device operations
671 * @supported_protocols: NFC protocols supported by the device
672 */
673struct nfc_dev *nfc_allocate_device(struct nfc_ops *ops,
674 u32 supported_protocols,
675 int tx_headroom, int tx_tailroom)
676{
677 static atomic_t dev_no = ATOMIC_INIT(0);
678 struct nfc_dev *dev;
679
680 if (!ops->start_poll || !ops->stop_poll || !ops->activate_target ||
681 !ops->deactivate_target || !ops->data_exchange)
682 return NULL;
683
684 if (!supported_protocols)
685 return NULL;
686
687 dev = kzalloc(sizeof(struct nfc_dev), GFP_KERNEL);
688 if (!dev)
689 return NULL;
690
691 dev->dev.class = &nfc_class;
692 dev->idx = atomic_inc_return(&dev_no) - 1;
693 dev_set_name(&dev->dev, "nfc%d", dev->idx);
694 device_initialize(&dev->dev);
695
696 dev->ops = ops;
697 dev->supported_protocols = supported_protocols;
698 dev->tx_headroom = tx_headroom;
699 dev->tx_tailroom = tx_tailroom;
700
701 nfc_genl_data_init(&dev->genl_data);
702
703
704 /* first generation must not be 0 */
705 dev->targets_generation = 1;
706
707 if (ops->check_presence) {
708 char name[32];
709 init_timer(&dev->check_pres_timer);
710 dev->check_pres_timer.data = (unsigned long)dev;
711 dev->check_pres_timer.function = nfc_check_pres_timeout;
712
713 INIT_WORK(&dev->check_pres_work, nfc_check_pres_work);
714 snprintf(name, sizeof(name), "nfc%d_check_pres_wq", dev->idx);
715 dev->check_pres_wq = alloc_workqueue(name, WQ_NON_REENTRANT |
716 WQ_UNBOUND |
717 WQ_MEM_RECLAIM, 1);
718 if (dev->check_pres_wq == NULL) {
719 kfree(dev);
720 return NULL;
721 }
722 }
723
724 return dev;
725}
726EXPORT_SYMBOL(nfc_allocate_device);
727
728/**
729 * nfc_register_device - register a nfc device in the nfc subsystem
730 *
731 * @dev: The nfc device to register
732 */
733int nfc_register_device(struct nfc_dev *dev)
734{
735 int rc;
736
737 pr_debug("dev_name=%s\n", dev_name(&dev->dev));
738
739 mutex_lock(&nfc_devlist_mutex);
740 nfc_devlist_generation++;
741 rc = device_add(&dev->dev);
742 mutex_unlock(&nfc_devlist_mutex);
743
744 if (rc < 0)
745 return rc;
746
747 rc = nfc_llcp_register_device(dev);
748 if (rc)
749 pr_err("Could not register llcp device\n");
750
751 rc = nfc_genl_device_added(dev);
752 if (rc)
753 pr_debug("The userspace won't be notified that the device %s was added\n",
754 dev_name(&dev->dev));
755
756 return 0;
757}
758EXPORT_SYMBOL(nfc_register_device);
759
760/**
761 * nfc_unregister_device - unregister a nfc device in the nfc subsystem
762 *
763 * @dev: The nfc device to unregister
764 */
765void nfc_unregister_device(struct nfc_dev *dev)
766{
767 int rc;
768
769 pr_debug("dev_name=%s\n", dev_name(&dev->dev));
770
771 mutex_lock(&nfc_devlist_mutex);
772 nfc_devlist_generation++;
773
774 /* lock to avoid unregistering a device while an operation
775 is in progress */
776 device_lock(&dev->dev);
777 device_del(&dev->dev);
778 device_unlock(&dev->dev);
779
780 mutex_unlock(&nfc_devlist_mutex);
781
782 nfc_llcp_unregister_device(dev);
783
784 rc = nfc_genl_device_removed(dev);
785 if (rc)
786 pr_debug("The userspace won't be notified that the device %s was removed\n",
787 dev_name(&dev->dev));
788
789}
790EXPORT_SYMBOL(nfc_unregister_device);
791
792static int __init nfc_init(void)
793{
794 int rc;
795
796 pr_info("NFC Core ver %s\n", VERSION);
797
798 rc = class_register(&nfc_class);
799 if (rc)
800 return rc;
801
802 rc = nfc_genl_init();
803 if (rc)
804 goto err_genl;
805
806 /* the first generation must not be 0 */
807 nfc_devlist_generation = 1;
808
809 rc = rawsock_init();
810 if (rc)
811 goto err_rawsock;
812
813 rc = nfc_llcp_init();
814 if (rc)
815 goto err_llcp_sock;
816
817 rc = af_nfc_init();
818 if (rc)
819 goto err_af_nfc;
820
821 return 0;
822
823err_af_nfc:
824 nfc_llcp_exit();
825err_llcp_sock:
826 rawsock_exit();
827err_rawsock:
828 nfc_genl_exit();
829err_genl:
830 class_unregister(&nfc_class);
831 return rc;
832}
833
834static void __exit nfc_exit(void)
835{
836 af_nfc_exit();
837 nfc_llcp_exit();
838 rawsock_exit();
839 nfc_genl_exit();
840 class_unregister(&nfc_class);
841}
842
843subsys_initcall(nfc_init);
844module_exit(nfc_exit);
845
846MODULE_AUTHOR("Lauro Ramos Venancio <lauro.venancio@openbossa.org>");
847MODULE_DESCRIPTION("NFC Core ver " VERSION);
848MODULE_VERSION(VERSION);
849MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2011 Instituto Nokia de Tecnologia
4 *
5 * Authors:
6 * Lauro Ramos Venancio <lauro.venancio@openbossa.org>
7 * Aloisio Almeida Jr <aloisio.almeida@openbossa.org>
8 */
9
10#define pr_fmt(fmt) KBUILD_MODNAME ": %s: " fmt, __func__
11
12#include <linux/init.h>
13#include <linux/kernel.h>
14#include <linux/module.h>
15#include <linux/slab.h>
16#include <linux/rfkill.h>
17#include <linux/nfc.h>
18
19#include <net/genetlink.h>
20
21#include "nfc.h"
22
23#define VERSION "0.1"
24
25#define NFC_CHECK_PRES_FREQ_MS 2000
26
27int nfc_devlist_generation;
28DEFINE_MUTEX(nfc_devlist_mutex);
29
30/* NFC device ID bitmap */
31static DEFINE_IDA(nfc_index_ida);
32
33int nfc_fw_download(struct nfc_dev *dev, const char *firmware_name)
34{
35 int rc = 0;
36
37 pr_debug("%s do firmware %s\n", dev_name(&dev->dev), firmware_name);
38
39 device_lock(&dev->dev);
40
41 if (dev->shutting_down) {
42 rc = -ENODEV;
43 goto error;
44 }
45
46 if (dev->dev_up) {
47 rc = -EBUSY;
48 goto error;
49 }
50
51 if (!dev->ops->fw_download) {
52 rc = -EOPNOTSUPP;
53 goto error;
54 }
55
56 dev->fw_download_in_progress = true;
57 rc = dev->ops->fw_download(dev, firmware_name);
58 if (rc)
59 dev->fw_download_in_progress = false;
60
61error:
62 device_unlock(&dev->dev);
63 return rc;
64}
65
66/**
67 * nfc_fw_download_done - inform that a firmware download was completed
68 *
69 * @dev: The nfc device to which firmware was downloaded
70 * @firmware_name: The firmware filename
71 * @result: The positive value of a standard errno value
72 */
73int nfc_fw_download_done(struct nfc_dev *dev, const char *firmware_name,
74 u32 result)
75{
76 dev->fw_download_in_progress = false;
77
78 return nfc_genl_fw_download_done(dev, firmware_name, result);
79}
80EXPORT_SYMBOL(nfc_fw_download_done);
81
82/**
83 * nfc_dev_up - turn on the NFC device
84 *
85 * @dev: The nfc device to be turned on
86 *
87 * The device remains up until the nfc_dev_down function is called.
88 */
89int nfc_dev_up(struct nfc_dev *dev)
90{
91 int rc = 0;
92
93 pr_debug("dev_name=%s\n", dev_name(&dev->dev));
94
95 device_lock(&dev->dev);
96
97 if (dev->shutting_down) {
98 rc = -ENODEV;
99 goto error;
100 }
101
102 if (dev->rfkill && rfkill_blocked(dev->rfkill)) {
103 rc = -ERFKILL;
104 goto error;
105 }
106
107 if (dev->fw_download_in_progress) {
108 rc = -EBUSY;
109 goto error;
110 }
111
112 if (dev->dev_up) {
113 rc = -EALREADY;
114 goto error;
115 }
116
117 if (dev->ops->dev_up)
118 rc = dev->ops->dev_up(dev);
119
120 if (!rc)
121 dev->dev_up = true;
122
123 /* We have to enable the device before discovering SEs */
124 if (dev->ops->discover_se && dev->ops->discover_se(dev))
125 pr_err("SE discovery failed\n");
126
127error:
128 device_unlock(&dev->dev);
129 return rc;
130}
131
132/**
133 * nfc_dev_down - turn off the NFC device
134 *
135 * @dev: The nfc device to be turned off
136 */
137int nfc_dev_down(struct nfc_dev *dev)
138{
139 int rc = 0;
140
141 pr_debug("dev_name=%s\n", dev_name(&dev->dev));
142
143 device_lock(&dev->dev);
144
145 if (dev->shutting_down) {
146 rc = -ENODEV;
147 goto error;
148 }
149
150 if (!dev->dev_up) {
151 rc = -EALREADY;
152 goto error;
153 }
154
155 if (dev->polling || dev->active_target) {
156 rc = -EBUSY;
157 goto error;
158 }
159
160 if (dev->ops->dev_down)
161 dev->ops->dev_down(dev);
162
163 dev->dev_up = false;
164
165error:
166 device_unlock(&dev->dev);
167 return rc;
168}
169
170static int nfc_rfkill_set_block(void *data, bool blocked)
171{
172 struct nfc_dev *dev = data;
173
174 pr_debug("%s blocked %d", dev_name(&dev->dev), blocked);
175
176 if (!blocked)
177 return 0;
178
179 nfc_dev_down(dev);
180
181 return 0;
182}
183
184static const struct rfkill_ops nfc_rfkill_ops = {
185 .set_block = nfc_rfkill_set_block,
186};
187
188/**
189 * nfc_start_poll - start polling for nfc targets
190 *
191 * @dev: The nfc device that must start polling
192 * @im_protocols: bitset of nfc initiator protocols to be used for polling
193 * @tm_protocols: bitset of nfc transport protocols to be used for polling
194 *
195 * The device remains polling for targets until a target is found or
196 * the nfc_stop_poll function is called.
197 */
198int nfc_start_poll(struct nfc_dev *dev, u32 im_protocols, u32 tm_protocols)
199{
200 int rc;
201
202 pr_debug("dev_name %s initiator protocols 0x%x target protocols 0x%x\n",
203 dev_name(&dev->dev), im_protocols, tm_protocols);
204
205 if (!im_protocols && !tm_protocols)
206 return -EINVAL;
207
208 device_lock(&dev->dev);
209
210 if (dev->shutting_down) {
211 rc = -ENODEV;
212 goto error;
213 }
214
215 if (!dev->dev_up) {
216 rc = -ENODEV;
217 goto error;
218 }
219
220 if (dev->polling) {
221 rc = -EBUSY;
222 goto error;
223 }
224
225 rc = dev->ops->start_poll(dev, im_protocols, tm_protocols);
226 if (!rc) {
227 dev->polling = true;
228 dev->rf_mode = NFC_RF_NONE;
229 }
230
231error:
232 device_unlock(&dev->dev);
233 return rc;
234}
235
236/**
237 * nfc_stop_poll - stop polling for nfc targets
238 *
239 * @dev: The nfc device that must stop polling
240 */
241int nfc_stop_poll(struct nfc_dev *dev)
242{
243 int rc = 0;
244
245 pr_debug("dev_name=%s\n", dev_name(&dev->dev));
246
247 device_lock(&dev->dev);
248
249 if (dev->shutting_down) {
250 rc = -ENODEV;
251 goto error;
252 }
253
254 if (!dev->polling) {
255 rc = -EINVAL;
256 goto error;
257 }
258
259 dev->ops->stop_poll(dev);
260 dev->polling = false;
261 dev->rf_mode = NFC_RF_NONE;
262
263error:
264 device_unlock(&dev->dev);
265 return rc;
266}
267
268static struct nfc_target *nfc_find_target(struct nfc_dev *dev, u32 target_idx)
269{
270 int i;
271
272 for (i = 0; i < dev->n_targets; i++) {
273 if (dev->targets[i].idx == target_idx)
274 return &dev->targets[i];
275 }
276
277 return NULL;
278}
279
280int nfc_dep_link_up(struct nfc_dev *dev, int target_index, u8 comm_mode)
281{
282 int rc = 0;
283 u8 *gb;
284 size_t gb_len;
285 struct nfc_target *target;
286
287 pr_debug("dev_name=%s comm %d\n", dev_name(&dev->dev), comm_mode);
288
289 if (!dev->ops->dep_link_up)
290 return -EOPNOTSUPP;
291
292 device_lock(&dev->dev);
293
294 if (dev->shutting_down) {
295 rc = -ENODEV;
296 goto error;
297 }
298
299 if (dev->dep_link_up == true) {
300 rc = -EALREADY;
301 goto error;
302 }
303
304 gb = nfc_llcp_general_bytes(dev, &gb_len);
305 if (gb_len > NFC_MAX_GT_LEN) {
306 rc = -EINVAL;
307 goto error;
308 }
309
310 target = nfc_find_target(dev, target_index);
311 if (target == NULL) {
312 rc = -ENOTCONN;
313 goto error;
314 }
315
316 rc = dev->ops->dep_link_up(dev, target, comm_mode, gb, gb_len);
317 if (!rc) {
318 dev->active_target = target;
319 dev->rf_mode = NFC_RF_INITIATOR;
320 }
321
322error:
323 device_unlock(&dev->dev);
324 return rc;
325}
326
327int nfc_dep_link_down(struct nfc_dev *dev)
328{
329 int rc = 0;
330
331 pr_debug("dev_name=%s\n", dev_name(&dev->dev));
332
333 if (!dev->ops->dep_link_down)
334 return -EOPNOTSUPP;
335
336 device_lock(&dev->dev);
337
338 if (dev->shutting_down) {
339 rc = -ENODEV;
340 goto error;
341 }
342
343 if (dev->dep_link_up == false) {
344 rc = -EALREADY;
345 goto error;
346 }
347
348 rc = dev->ops->dep_link_down(dev);
349 if (!rc) {
350 dev->dep_link_up = false;
351 dev->active_target = NULL;
352 dev->rf_mode = NFC_RF_NONE;
353 nfc_llcp_mac_is_down(dev);
354 nfc_genl_dep_link_down_event(dev);
355 }
356
357error:
358 device_unlock(&dev->dev);
359
360 return rc;
361}
362
363int nfc_dep_link_is_up(struct nfc_dev *dev, u32 target_idx,
364 u8 comm_mode, u8 rf_mode)
365{
366 dev->dep_link_up = true;
367
368 if (!dev->active_target && rf_mode == NFC_RF_INITIATOR) {
369 struct nfc_target *target;
370
371 target = nfc_find_target(dev, target_idx);
372 if (target == NULL)
373 return -ENOTCONN;
374
375 dev->active_target = target;
376 }
377
378 dev->polling = false;
379 dev->rf_mode = rf_mode;
380
381 nfc_llcp_mac_is_up(dev, target_idx, comm_mode, rf_mode);
382
383 return nfc_genl_dep_link_up_event(dev, target_idx, comm_mode, rf_mode);
384}
385EXPORT_SYMBOL(nfc_dep_link_is_up);
386
387/**
388 * nfc_activate_target - prepare the target for data exchange
389 *
390 * @dev: The nfc device that found the target
391 * @target_idx: index of the target that must be activated
392 * @protocol: nfc protocol that will be used for data exchange
393 */
394int nfc_activate_target(struct nfc_dev *dev, u32 target_idx, u32 protocol)
395{
396 int rc;
397 struct nfc_target *target;
398
399 pr_debug("dev_name=%s target_idx=%u protocol=%u\n",
400 dev_name(&dev->dev), target_idx, protocol);
401
402 device_lock(&dev->dev);
403
404 if (dev->shutting_down) {
405 rc = -ENODEV;
406 goto error;
407 }
408
409 if (dev->active_target) {
410 rc = -EBUSY;
411 goto error;
412 }
413
414 target = nfc_find_target(dev, target_idx);
415 if (target == NULL) {
416 rc = -ENOTCONN;
417 goto error;
418 }
419
420 rc = dev->ops->activate_target(dev, target, protocol);
421 if (!rc) {
422 dev->active_target = target;
423 dev->rf_mode = NFC_RF_INITIATOR;
424
425 if (dev->ops->check_presence && !dev->shutting_down)
426 mod_timer(&dev->check_pres_timer, jiffies +
427 msecs_to_jiffies(NFC_CHECK_PRES_FREQ_MS));
428 }
429
430error:
431 device_unlock(&dev->dev);
432 return rc;
433}
434
435/**
436 * nfc_deactivate_target - deactivate a nfc target
437 *
438 * @dev: The nfc device that found the target
439 * @target_idx: index of the target that must be deactivated
440 * @mode: idle or sleep?
441 */
442int nfc_deactivate_target(struct nfc_dev *dev, u32 target_idx, u8 mode)
443{
444 int rc = 0;
445
446 pr_debug("dev_name=%s target_idx=%u\n",
447 dev_name(&dev->dev), target_idx);
448
449 device_lock(&dev->dev);
450
451 if (dev->shutting_down) {
452 rc = -ENODEV;
453 goto error;
454 }
455
456 if (dev->active_target == NULL) {
457 rc = -ENOTCONN;
458 goto error;
459 }
460
461 if (dev->active_target->idx != target_idx) {
462 rc = -ENOTCONN;
463 goto error;
464 }
465
466 if (dev->ops->check_presence)
467 del_timer_sync(&dev->check_pres_timer);
468
469 dev->ops->deactivate_target(dev, dev->active_target, mode);
470 dev->active_target = NULL;
471
472error:
473 device_unlock(&dev->dev);
474 return rc;
475}
476
477/**
478 * nfc_data_exchange - transceive data
479 *
480 * @dev: The nfc device that found the target
481 * @target_idx: index of the target
482 * @skb: data to be sent
483 * @cb: callback called when the response is received
484 * @cb_context: parameter for the callback function
485 *
486 * The user must wait for the callback before calling this function again.
487 */
488int nfc_data_exchange(struct nfc_dev *dev, u32 target_idx, struct sk_buff *skb,
489 data_exchange_cb_t cb, void *cb_context)
490{
491 int rc;
492
493 pr_debug("dev_name=%s target_idx=%u skb->len=%u\n",
494 dev_name(&dev->dev), target_idx, skb->len);
495
496 device_lock(&dev->dev);
497
498 if (dev->shutting_down) {
499 rc = -ENODEV;
500 kfree_skb(skb);
501 goto error;
502 }
503
504 if (dev->rf_mode == NFC_RF_INITIATOR && dev->active_target != NULL) {
505 if (dev->active_target->idx != target_idx) {
506 rc = -EADDRNOTAVAIL;
507 kfree_skb(skb);
508 goto error;
509 }
510
511 if (dev->ops->check_presence)
512 del_timer_sync(&dev->check_pres_timer);
513
514 rc = dev->ops->im_transceive(dev, dev->active_target, skb, cb,
515 cb_context);
516
517 if (!rc && dev->ops->check_presence && !dev->shutting_down)
518 mod_timer(&dev->check_pres_timer, jiffies +
519 msecs_to_jiffies(NFC_CHECK_PRES_FREQ_MS));
520 } else if (dev->rf_mode == NFC_RF_TARGET && dev->ops->tm_send != NULL) {
521 rc = dev->ops->tm_send(dev, skb);
522 } else {
523 rc = -ENOTCONN;
524 kfree_skb(skb);
525 goto error;
526 }
527
528
529error:
530 device_unlock(&dev->dev);
531 return rc;
532}
533
534struct nfc_se *nfc_find_se(struct nfc_dev *dev, u32 se_idx)
535{
536 struct nfc_se *se;
537
538 list_for_each_entry(se, &dev->secure_elements, list)
539 if (se->idx == se_idx)
540 return se;
541
542 return NULL;
543}
544EXPORT_SYMBOL(nfc_find_se);
545
546int nfc_enable_se(struct nfc_dev *dev, u32 se_idx)
547{
548 struct nfc_se *se;
549 int rc;
550
551 pr_debug("%s se index %d\n", dev_name(&dev->dev), se_idx);
552
553 device_lock(&dev->dev);
554
555 if (dev->shutting_down) {
556 rc = -ENODEV;
557 goto error;
558 }
559
560 if (!dev->dev_up) {
561 rc = -ENODEV;
562 goto error;
563 }
564
565 if (dev->polling) {
566 rc = -EBUSY;
567 goto error;
568 }
569
570 if (!dev->ops->enable_se || !dev->ops->disable_se) {
571 rc = -EOPNOTSUPP;
572 goto error;
573 }
574
575 se = nfc_find_se(dev, se_idx);
576 if (!se) {
577 rc = -EINVAL;
578 goto error;
579 }
580
581 if (se->state == NFC_SE_ENABLED) {
582 rc = -EALREADY;
583 goto error;
584 }
585
586 rc = dev->ops->enable_se(dev, se_idx);
587 if (rc >= 0)
588 se->state = NFC_SE_ENABLED;
589
590error:
591 device_unlock(&dev->dev);
592 return rc;
593}
594
595int nfc_disable_se(struct nfc_dev *dev, u32 se_idx)
596{
597 struct nfc_se *se;
598 int rc;
599
600 pr_debug("%s se index %d\n", dev_name(&dev->dev), se_idx);
601
602 device_lock(&dev->dev);
603
604 if (dev->shutting_down) {
605 rc = -ENODEV;
606 goto error;
607 }
608
609 if (!dev->dev_up) {
610 rc = -ENODEV;
611 goto error;
612 }
613
614 if (!dev->ops->enable_se || !dev->ops->disable_se) {
615 rc = -EOPNOTSUPP;
616 goto error;
617 }
618
619 se = nfc_find_se(dev, se_idx);
620 if (!se) {
621 rc = -EINVAL;
622 goto error;
623 }
624
625 if (se->state == NFC_SE_DISABLED) {
626 rc = -EALREADY;
627 goto error;
628 }
629
630 rc = dev->ops->disable_se(dev, se_idx);
631 if (rc >= 0)
632 se->state = NFC_SE_DISABLED;
633
634error:
635 device_unlock(&dev->dev);
636 return rc;
637}
638
639int nfc_set_remote_general_bytes(struct nfc_dev *dev, const u8 *gb, u8 gb_len)
640{
641 pr_debug("dev_name=%s gb_len=%d\n", dev_name(&dev->dev), gb_len);
642
643 return nfc_llcp_set_remote_gb(dev, gb, gb_len);
644}
645EXPORT_SYMBOL(nfc_set_remote_general_bytes);
646
647u8 *nfc_get_local_general_bytes(struct nfc_dev *dev, size_t *gb_len)
648{
649 pr_debug("dev_name=%s\n", dev_name(&dev->dev));
650
651 return nfc_llcp_general_bytes(dev, gb_len);
652}
653EXPORT_SYMBOL(nfc_get_local_general_bytes);
654
655int nfc_tm_data_received(struct nfc_dev *dev, struct sk_buff *skb)
656{
657 /* Only LLCP target mode for now */
658 if (dev->dep_link_up == false) {
659 kfree_skb(skb);
660 return -ENOLINK;
661 }
662
663 return nfc_llcp_data_received(dev, skb);
664}
665EXPORT_SYMBOL(nfc_tm_data_received);
666
667int nfc_tm_activated(struct nfc_dev *dev, u32 protocol, u8 comm_mode,
668 const u8 *gb, size_t gb_len)
669{
670 int rc;
671
672 device_lock(&dev->dev);
673
674 dev->polling = false;
675
676 if (gb != NULL) {
677 rc = nfc_set_remote_general_bytes(dev, gb, gb_len);
678 if (rc < 0)
679 goto out;
680 }
681
682 dev->rf_mode = NFC_RF_TARGET;
683
684 if (protocol == NFC_PROTO_NFC_DEP_MASK)
685 nfc_dep_link_is_up(dev, 0, comm_mode, NFC_RF_TARGET);
686
687 rc = nfc_genl_tm_activated(dev, protocol);
688
689out:
690 device_unlock(&dev->dev);
691
692 return rc;
693}
694EXPORT_SYMBOL(nfc_tm_activated);
695
696int nfc_tm_deactivated(struct nfc_dev *dev)
697{
698 dev->dep_link_up = false;
699 dev->rf_mode = NFC_RF_NONE;
700
701 return nfc_genl_tm_deactivated(dev);
702}
703EXPORT_SYMBOL(nfc_tm_deactivated);
704
705/**
706 * nfc_alloc_send_skb - allocate a skb for data exchange responses
707 *
708 * @dev: device sending the response
709 * @sk: socket sending the response
710 * @flags: MSG_DONTWAIT flag
711 * @size: size to allocate
712 * @err: pointer to memory to store the error code
713 */
714struct sk_buff *nfc_alloc_send_skb(struct nfc_dev *dev, struct sock *sk,
715 unsigned int flags, unsigned int size,
716 unsigned int *err)
717{
718 struct sk_buff *skb;
719 unsigned int total_size;
720
721 total_size = size +
722 dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
723
724 skb = sock_alloc_send_skb(sk, total_size, flags & MSG_DONTWAIT, err);
725 if (skb)
726 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
727
728 return skb;
729}
730
731/**
732 * nfc_alloc_recv_skb - allocate a skb for data exchange responses
733 *
734 * @size: size to allocate
735 * @gfp: gfp flags
736 */
737struct sk_buff *nfc_alloc_recv_skb(unsigned int size, gfp_t gfp)
738{
739 struct sk_buff *skb;
740 unsigned int total_size;
741
742 total_size = size + 1;
743 skb = alloc_skb(total_size, gfp);
744
745 if (skb)
746 skb_reserve(skb, 1);
747
748 return skb;
749}
750EXPORT_SYMBOL(nfc_alloc_recv_skb);
751
752/**
753 * nfc_targets_found - inform that targets were found
754 *
755 * @dev: The nfc device that found the targets
756 * @targets: array of nfc targets found
757 * @n_targets: targets array size
758 *
759 * The device driver must call this function when one or many nfc targets
760 * are found. After calling this function, the device driver must stop
761 * polling for targets.
762 * NOTE: This function can be called with targets=NULL and n_targets=0 to
763 * notify a driver error, meaning that the polling operation cannot complete.
764 * IMPORTANT: this function must not be called from an atomic context.
765 * In addition, it must also not be called from a context that would prevent
766 * the NFC Core to call other nfc ops entry point concurrently.
767 */
768int nfc_targets_found(struct nfc_dev *dev,
769 struct nfc_target *targets, int n_targets)
770{
771 int i;
772
773 pr_debug("dev_name=%s n_targets=%d\n", dev_name(&dev->dev), n_targets);
774
775 for (i = 0; i < n_targets; i++)
776 targets[i].idx = dev->target_next_idx++;
777
778 device_lock(&dev->dev);
779
780 if (dev->polling == false) {
781 device_unlock(&dev->dev);
782 return 0;
783 }
784
785 dev->polling = false;
786
787 dev->targets_generation++;
788
789 kfree(dev->targets);
790 dev->targets = NULL;
791
792 if (targets) {
793 dev->targets = kmemdup(targets,
794 n_targets * sizeof(struct nfc_target),
795 GFP_ATOMIC);
796
797 if (!dev->targets) {
798 dev->n_targets = 0;
799 device_unlock(&dev->dev);
800 return -ENOMEM;
801 }
802 }
803
804 dev->n_targets = n_targets;
805 device_unlock(&dev->dev);
806
807 nfc_genl_targets_found(dev);
808
809 return 0;
810}
811EXPORT_SYMBOL(nfc_targets_found);
812
813/**
814 * nfc_target_lost - inform that an activated target went out of field
815 *
816 * @dev: The nfc device that had the activated target in field
817 * @target_idx: the nfc index of the target
818 *
819 * The device driver must call this function when the activated target
820 * goes out of the field.
821 * IMPORTANT: this function must not be called from an atomic context.
822 * In addition, it must also not be called from a context that would prevent
823 * the NFC Core to call other nfc ops entry point concurrently.
824 */
825int nfc_target_lost(struct nfc_dev *dev, u32 target_idx)
826{
827 const struct nfc_target *tg;
828 int i;
829
830 pr_debug("dev_name %s n_target %d\n", dev_name(&dev->dev), target_idx);
831
832 device_lock(&dev->dev);
833
834 for (i = 0; i < dev->n_targets; i++) {
835 tg = &dev->targets[i];
836 if (tg->idx == target_idx)
837 break;
838 }
839
840 if (i == dev->n_targets) {
841 device_unlock(&dev->dev);
842 return -EINVAL;
843 }
844
845 dev->targets_generation++;
846 dev->n_targets--;
847 dev->active_target = NULL;
848
849 if (dev->n_targets) {
850 memcpy(&dev->targets[i], &dev->targets[i + 1],
851 (dev->n_targets - i) * sizeof(struct nfc_target));
852 } else {
853 kfree(dev->targets);
854 dev->targets = NULL;
855 }
856
857 device_unlock(&dev->dev);
858
859 nfc_genl_target_lost(dev, target_idx);
860
861 return 0;
862}
863EXPORT_SYMBOL(nfc_target_lost);
864
865inline void nfc_driver_failure(struct nfc_dev *dev, int err)
866{
867 nfc_targets_found(dev, NULL, 0);
868}
869EXPORT_SYMBOL(nfc_driver_failure);
870
871int nfc_add_se(struct nfc_dev *dev, u32 se_idx, u16 type)
872{
873 struct nfc_se *se;
874 int rc;
875
876 pr_debug("%s se index %d\n", dev_name(&dev->dev), se_idx);
877
878 se = nfc_find_se(dev, se_idx);
879 if (se)
880 return -EALREADY;
881
882 se = kzalloc(sizeof(struct nfc_se), GFP_KERNEL);
883 if (!se)
884 return -ENOMEM;
885
886 se->idx = se_idx;
887 se->type = type;
888 se->state = NFC_SE_DISABLED;
889 INIT_LIST_HEAD(&se->list);
890
891 list_add(&se->list, &dev->secure_elements);
892
893 rc = nfc_genl_se_added(dev, se_idx, type);
894 if (rc < 0) {
895 list_del(&se->list);
896 kfree(se);
897
898 return rc;
899 }
900
901 return 0;
902}
903EXPORT_SYMBOL(nfc_add_se);
904
905int nfc_remove_se(struct nfc_dev *dev, u32 se_idx)
906{
907 struct nfc_se *se, *n;
908 int rc;
909
910 pr_debug("%s se index %d\n", dev_name(&dev->dev), se_idx);
911
912 list_for_each_entry_safe(se, n, &dev->secure_elements, list)
913 if (se->idx == se_idx) {
914 rc = nfc_genl_se_removed(dev, se_idx);
915 if (rc < 0)
916 return rc;
917
918 list_del(&se->list);
919 kfree(se);
920
921 return 0;
922 }
923
924 return -EINVAL;
925}
926EXPORT_SYMBOL(nfc_remove_se);
927
928int nfc_se_transaction(struct nfc_dev *dev, u8 se_idx,
929 struct nfc_evt_transaction *evt_transaction)
930{
931 int rc;
932
933 pr_debug("transaction: %x\n", se_idx);
934
935 device_lock(&dev->dev);
936
937 if (!evt_transaction) {
938 rc = -EPROTO;
939 goto out;
940 }
941
942 rc = nfc_genl_se_transaction(dev, se_idx, evt_transaction);
943out:
944 device_unlock(&dev->dev);
945 return rc;
946}
947EXPORT_SYMBOL(nfc_se_transaction);
948
949int nfc_se_connectivity(struct nfc_dev *dev, u8 se_idx)
950{
951 int rc;
952
953 pr_debug("connectivity: %x\n", se_idx);
954
955 device_lock(&dev->dev);
956 rc = nfc_genl_se_connectivity(dev, se_idx);
957 device_unlock(&dev->dev);
958 return rc;
959}
960EXPORT_SYMBOL(nfc_se_connectivity);
961
962static void nfc_release(struct device *d)
963{
964 struct nfc_dev *dev = to_nfc_dev(d);
965 struct nfc_se *se, *n;
966
967 pr_debug("dev_name=%s\n", dev_name(&dev->dev));
968
969 nfc_genl_data_exit(&dev->genl_data);
970 kfree(dev->targets);
971
972 list_for_each_entry_safe(se, n, &dev->secure_elements, list) {
973 nfc_genl_se_removed(dev, se->idx);
974 list_del(&se->list);
975 kfree(se);
976 }
977
978 ida_free(&nfc_index_ida, dev->idx);
979
980 kfree(dev);
981}
982
983static void nfc_check_pres_work(struct work_struct *work)
984{
985 struct nfc_dev *dev = container_of(work, struct nfc_dev,
986 check_pres_work);
987 int rc;
988
989 device_lock(&dev->dev);
990
991 if (dev->active_target && timer_pending(&dev->check_pres_timer) == 0) {
992 rc = dev->ops->check_presence(dev, dev->active_target);
993 if (rc == -EOPNOTSUPP)
994 goto exit;
995 if (rc) {
996 u32 active_target_idx = dev->active_target->idx;
997 device_unlock(&dev->dev);
998 nfc_target_lost(dev, active_target_idx);
999 return;
1000 }
1001
1002 if (!dev->shutting_down)
1003 mod_timer(&dev->check_pres_timer, jiffies +
1004 msecs_to_jiffies(NFC_CHECK_PRES_FREQ_MS));
1005 }
1006
1007exit:
1008 device_unlock(&dev->dev);
1009}
1010
1011static void nfc_check_pres_timeout(struct timer_list *t)
1012{
1013 struct nfc_dev *dev = from_timer(dev, t, check_pres_timer);
1014
1015 schedule_work(&dev->check_pres_work);
1016}
1017
1018struct class nfc_class = {
1019 .name = "nfc",
1020 .dev_release = nfc_release,
1021};
1022EXPORT_SYMBOL(nfc_class);
1023
1024static int match_idx(struct device *d, const void *data)
1025{
1026 struct nfc_dev *dev = to_nfc_dev(d);
1027 const unsigned int *idx = data;
1028
1029 return dev->idx == *idx;
1030}
1031
1032struct nfc_dev *nfc_get_device(unsigned int idx)
1033{
1034 struct device *d;
1035
1036 d = class_find_device(&nfc_class, NULL, &idx, match_idx);
1037 if (!d)
1038 return NULL;
1039
1040 return to_nfc_dev(d);
1041}
1042
1043/**
1044 * nfc_allocate_device - allocate a new nfc device
1045 *
1046 * @ops: device operations
1047 * @supported_protocols: NFC protocols supported by the device
1048 * @tx_headroom: reserved space at beginning of skb
1049 * @tx_tailroom: reserved space at end of skb
1050 */
1051struct nfc_dev *nfc_allocate_device(const struct nfc_ops *ops,
1052 u32 supported_protocols,
1053 int tx_headroom, int tx_tailroom)
1054{
1055 struct nfc_dev *dev;
1056 int rc;
1057
1058 if (!ops->start_poll || !ops->stop_poll || !ops->activate_target ||
1059 !ops->deactivate_target || !ops->im_transceive)
1060 return NULL;
1061
1062 if (!supported_protocols)
1063 return NULL;
1064
1065 dev = kzalloc(sizeof(struct nfc_dev), GFP_KERNEL);
1066 if (!dev)
1067 return NULL;
1068
1069 rc = ida_alloc(&nfc_index_ida, GFP_KERNEL);
1070 if (rc < 0)
1071 goto err_free_dev;
1072 dev->idx = rc;
1073
1074 dev->dev.class = &nfc_class;
1075 dev_set_name(&dev->dev, "nfc%d", dev->idx);
1076 device_initialize(&dev->dev);
1077
1078 dev->ops = ops;
1079 dev->supported_protocols = supported_protocols;
1080 dev->tx_headroom = tx_headroom;
1081 dev->tx_tailroom = tx_tailroom;
1082 INIT_LIST_HEAD(&dev->secure_elements);
1083
1084 nfc_genl_data_init(&dev->genl_data);
1085
1086 dev->rf_mode = NFC_RF_NONE;
1087
1088 /* first generation must not be 0 */
1089 dev->targets_generation = 1;
1090
1091 if (ops->check_presence) {
1092 timer_setup(&dev->check_pres_timer, nfc_check_pres_timeout, 0);
1093 INIT_WORK(&dev->check_pres_work, nfc_check_pres_work);
1094 }
1095
1096 return dev;
1097
1098err_free_dev:
1099 kfree(dev);
1100
1101 return NULL;
1102}
1103EXPORT_SYMBOL(nfc_allocate_device);
1104
1105/**
1106 * nfc_register_device - register a nfc device in the nfc subsystem
1107 *
1108 * @dev: The nfc device to register
1109 */
1110int nfc_register_device(struct nfc_dev *dev)
1111{
1112 int rc;
1113
1114 pr_debug("dev_name=%s\n", dev_name(&dev->dev));
1115
1116 mutex_lock(&nfc_devlist_mutex);
1117 nfc_devlist_generation++;
1118 rc = device_add(&dev->dev);
1119 mutex_unlock(&nfc_devlist_mutex);
1120
1121 if (rc < 0)
1122 return rc;
1123
1124 rc = nfc_llcp_register_device(dev);
1125 if (rc)
1126 pr_err("Could not register llcp device\n");
1127
1128 device_lock(&dev->dev);
1129 dev->rfkill = rfkill_alloc(dev_name(&dev->dev), &dev->dev,
1130 RFKILL_TYPE_NFC, &nfc_rfkill_ops, dev);
1131 if (dev->rfkill) {
1132 if (rfkill_register(dev->rfkill) < 0) {
1133 rfkill_destroy(dev->rfkill);
1134 dev->rfkill = NULL;
1135 }
1136 }
1137 dev->shutting_down = false;
1138 device_unlock(&dev->dev);
1139
1140 rc = nfc_genl_device_added(dev);
1141 if (rc)
1142 pr_debug("The userspace won't be notified that the device %s was added\n",
1143 dev_name(&dev->dev));
1144
1145 return 0;
1146}
1147EXPORT_SYMBOL(nfc_register_device);
1148
1149/**
1150 * nfc_unregister_device - unregister a nfc device in the nfc subsystem
1151 *
1152 * @dev: The nfc device to unregister
1153 */
1154void nfc_unregister_device(struct nfc_dev *dev)
1155{
1156 int rc;
1157
1158 pr_debug("dev_name=%s\n", dev_name(&dev->dev));
1159
1160 rc = nfc_genl_device_removed(dev);
1161 if (rc)
1162 pr_debug("The userspace won't be notified that the device %s "
1163 "was removed\n", dev_name(&dev->dev));
1164
1165 device_lock(&dev->dev);
1166 if (dev->rfkill) {
1167 rfkill_unregister(dev->rfkill);
1168 rfkill_destroy(dev->rfkill);
1169 dev->rfkill = NULL;
1170 }
1171 dev->shutting_down = true;
1172 device_unlock(&dev->dev);
1173
1174 if (dev->ops->check_presence) {
1175 del_timer_sync(&dev->check_pres_timer);
1176 cancel_work_sync(&dev->check_pres_work);
1177 }
1178
1179 nfc_llcp_unregister_device(dev);
1180
1181 mutex_lock(&nfc_devlist_mutex);
1182 nfc_devlist_generation++;
1183 device_del(&dev->dev);
1184 mutex_unlock(&nfc_devlist_mutex);
1185}
1186EXPORT_SYMBOL(nfc_unregister_device);
1187
1188static int __init nfc_init(void)
1189{
1190 int rc;
1191
1192 pr_info("NFC Core ver %s\n", VERSION);
1193
1194 rc = class_register(&nfc_class);
1195 if (rc)
1196 return rc;
1197
1198 rc = nfc_genl_init();
1199 if (rc)
1200 goto err_genl;
1201
1202 /* the first generation must not be 0 */
1203 nfc_devlist_generation = 1;
1204
1205 rc = rawsock_init();
1206 if (rc)
1207 goto err_rawsock;
1208
1209 rc = nfc_llcp_init();
1210 if (rc)
1211 goto err_llcp_sock;
1212
1213 rc = af_nfc_init();
1214 if (rc)
1215 goto err_af_nfc;
1216
1217 return 0;
1218
1219err_af_nfc:
1220 nfc_llcp_exit();
1221err_llcp_sock:
1222 rawsock_exit();
1223err_rawsock:
1224 nfc_genl_exit();
1225err_genl:
1226 class_unregister(&nfc_class);
1227 return rc;
1228}
1229
1230static void __exit nfc_exit(void)
1231{
1232 af_nfc_exit();
1233 nfc_llcp_exit();
1234 rawsock_exit();
1235 nfc_genl_exit();
1236 class_unregister(&nfc_class);
1237}
1238
1239subsys_initcall(nfc_init);
1240module_exit(nfc_exit);
1241
1242MODULE_AUTHOR("Lauro Ramos Venancio <lauro.venancio@openbossa.org>");
1243MODULE_DESCRIPTION("NFC Core ver " VERSION);
1244MODULE_VERSION(VERSION);
1245MODULE_LICENSE("GPL");
1246MODULE_ALIAS_NETPROTO(PF_NFC);
1247MODULE_ALIAS_GENL_FAMILY(NFC_GENL_NAME);