Commit | Line | Data |
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3e256b8f LRV |
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 | ||
ed1e0ad8 JP |
24 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
25 | ||
3e256b8f LRV |
26 | #include <linux/init.h> |
27 | #include <linux/kernel.h> | |
28 | #include <linux/module.h> | |
29 | #include <linux/slab.h> | |
30 | ||
31 | #include "nfc.h" | |
32 | ||
33 | #define VERSION "0.1" | |
34 | ||
35 | int nfc_devlist_generation; | |
36 | DEFINE_MUTEX(nfc_devlist_mutex); | |
37 | ||
8b3fe7b5 IE |
38 | /** |
39 | * nfc_dev_up - turn on the NFC device | |
40 | * | |
41 | * @dev: The nfc device to be turned on | |
42 | * | |
43 | * The device remains up until the nfc_dev_down function is called. | |
44 | */ | |
45 | int nfc_dev_up(struct nfc_dev *dev) | |
46 | { | |
47 | int rc = 0; | |
48 | ||
20c239c1 | 49 | pr_debug("dev_name=%s\n", dev_name(&dev->dev)); |
8b3fe7b5 IE |
50 | |
51 | device_lock(&dev->dev); | |
52 | ||
53 | if (!device_is_registered(&dev->dev)) { | |
54 | rc = -ENODEV; | |
55 | goto error; | |
56 | } | |
57 | ||
58 | if (dev->dev_up) { | |
59 | rc = -EALREADY; | |
60 | goto error; | |
61 | } | |
62 | ||
63 | if (dev->ops->dev_up) | |
64 | rc = dev->ops->dev_up(dev); | |
65 | ||
66 | if (!rc) | |
67 | dev->dev_up = true; | |
68 | ||
69 | error: | |
70 | device_unlock(&dev->dev); | |
71 | return rc; | |
72 | } | |
73 | ||
74 | /** | |
75 | * nfc_dev_down - turn off the NFC device | |
76 | * | |
77 | * @dev: The nfc device to be turned off | |
78 | */ | |
79 | int nfc_dev_down(struct nfc_dev *dev) | |
80 | { | |
81 | int rc = 0; | |
82 | ||
20c239c1 | 83 | pr_debug("dev_name=%s\n", dev_name(&dev->dev)); |
8b3fe7b5 IE |
84 | |
85 | device_lock(&dev->dev); | |
86 | ||
87 | if (!device_is_registered(&dev->dev)) { | |
88 | rc = -ENODEV; | |
89 | goto error; | |
90 | } | |
91 | ||
92 | if (!dev->dev_up) { | |
93 | rc = -EALREADY; | |
94 | goto error; | |
95 | } | |
96 | ||
97 | if (dev->polling || dev->remote_activated) { | |
98 | rc = -EBUSY; | |
99 | goto error; | |
100 | } | |
101 | ||
102 | if (dev->ops->dev_down) | |
103 | dev->ops->dev_down(dev); | |
104 | ||
105 | dev->dev_up = false; | |
106 | ||
107 | error: | |
108 | device_unlock(&dev->dev); | |
109 | return rc; | |
110 | } | |
111 | ||
3e256b8f LRV |
112 | /** |
113 | * nfc_start_poll - start polling for nfc targets | |
114 | * | |
115 | * @dev: The nfc device that must start polling | |
116 | * @protocols: bitset of nfc protocols that must be used for polling | |
117 | * | |
118 | * The device remains polling for targets until a target is found or | |
119 | * the nfc_stop_poll function is called. | |
120 | */ | |
121 | int nfc_start_poll(struct nfc_dev *dev, u32 protocols) | |
122 | { | |
123 | int rc; | |
124 | ||
20c239c1 JP |
125 | pr_debug("dev_name=%s protocols=0x%x\n", |
126 | dev_name(&dev->dev), protocols); | |
3e256b8f LRV |
127 | |
128 | if (!protocols) | |
129 | return -EINVAL; | |
130 | ||
131 | device_lock(&dev->dev); | |
132 | ||
133 | if (!device_is_registered(&dev->dev)) { | |
134 | rc = -ENODEV; | |
135 | goto error; | |
136 | } | |
137 | ||
138 | if (dev->polling) { | |
139 | rc = -EBUSY; | |
140 | goto error; | |
141 | } | |
142 | ||
143 | rc = dev->ops->start_poll(dev, protocols); | |
144 | if (!rc) | |
145 | dev->polling = true; | |
146 | ||
147 | error: | |
148 | device_unlock(&dev->dev); | |
149 | return rc; | |
150 | } | |
151 | ||
152 | /** | |
153 | * nfc_stop_poll - stop polling for nfc targets | |
154 | * | |
155 | * @dev: The nfc device that must stop polling | |
156 | */ | |
157 | int nfc_stop_poll(struct nfc_dev *dev) | |
158 | { | |
159 | int rc = 0; | |
160 | ||
20c239c1 | 161 | pr_debug("dev_name=%s\n", dev_name(&dev->dev)); |
3e256b8f LRV |
162 | |
163 | device_lock(&dev->dev); | |
164 | ||
165 | if (!device_is_registered(&dev->dev)) { | |
166 | rc = -ENODEV; | |
167 | goto error; | |
168 | } | |
169 | ||
170 | if (!dev->polling) { | |
171 | rc = -EINVAL; | |
172 | goto error; | |
173 | } | |
174 | ||
175 | dev->ops->stop_poll(dev); | |
176 | dev->polling = false; | |
177 | ||
178 | error: | |
179 | device_unlock(&dev->dev); | |
180 | return rc; | |
181 | } | |
182 | ||
183 | /** | |
184 | * nfc_activate_target - prepare the target for data exchange | |
185 | * | |
186 | * @dev: The nfc device that found the target | |
187 | * @target_idx: index of the target that must be activated | |
188 | * @protocol: nfc protocol that will be used for data exchange | |
189 | */ | |
190 | int nfc_activate_target(struct nfc_dev *dev, u32 target_idx, u32 protocol) | |
191 | { | |
192 | int rc; | |
193 | ||
20c239c1 JP |
194 | pr_debug("dev_name=%s target_idx=%u protocol=%u\n", |
195 | dev_name(&dev->dev), target_idx, protocol); | |
3e256b8f LRV |
196 | |
197 | device_lock(&dev->dev); | |
198 | ||
199 | if (!device_is_registered(&dev->dev)) { | |
200 | rc = -ENODEV; | |
201 | goto error; | |
202 | } | |
203 | ||
204 | rc = dev->ops->activate_target(dev, target_idx, protocol); | |
8b3fe7b5 IE |
205 | if (!rc) |
206 | dev->remote_activated = true; | |
3e256b8f LRV |
207 | |
208 | error: | |
209 | device_unlock(&dev->dev); | |
210 | return rc; | |
211 | } | |
212 | ||
213 | /** | |
214 | * nfc_deactivate_target - deactivate a nfc target | |
215 | * | |
216 | * @dev: The nfc device that found the target | |
217 | * @target_idx: index of the target that must be deactivated | |
218 | */ | |
219 | int nfc_deactivate_target(struct nfc_dev *dev, u32 target_idx) | |
220 | { | |
221 | int rc = 0; | |
222 | ||
20c239c1 JP |
223 | pr_debug("dev_name=%s target_idx=%u\n", |
224 | dev_name(&dev->dev), target_idx); | |
3e256b8f LRV |
225 | |
226 | device_lock(&dev->dev); | |
227 | ||
228 | if (!device_is_registered(&dev->dev)) { | |
229 | rc = -ENODEV; | |
230 | goto error; | |
231 | } | |
232 | ||
233 | dev->ops->deactivate_target(dev, target_idx); | |
8b3fe7b5 | 234 | dev->remote_activated = false; |
3e256b8f LRV |
235 | |
236 | error: | |
237 | device_unlock(&dev->dev); | |
238 | return rc; | |
239 | } | |
240 | ||
241 | /** | |
242 | * nfc_data_exchange - transceive data | |
243 | * | |
244 | * @dev: The nfc device that found the target | |
245 | * @target_idx: index of the target | |
246 | * @skb: data to be sent | |
247 | * @cb: callback called when the response is received | |
248 | * @cb_context: parameter for the callback function | |
249 | * | |
250 | * The user must wait for the callback before calling this function again. | |
251 | */ | |
252 | int nfc_data_exchange(struct nfc_dev *dev, u32 target_idx, | |
253 | struct sk_buff *skb, | |
254 | data_exchange_cb_t cb, | |
255 | void *cb_context) | |
256 | { | |
257 | int rc; | |
258 | ||
20c239c1 JP |
259 | pr_debug("dev_name=%s target_idx=%u skb->len=%u\n", |
260 | dev_name(&dev->dev), target_idx, skb->len); | |
3e256b8f LRV |
261 | |
262 | device_lock(&dev->dev); | |
263 | ||
264 | if (!device_is_registered(&dev->dev)) { | |
265 | rc = -ENODEV; | |
266 | kfree_skb(skb); | |
267 | goto error; | |
268 | } | |
269 | ||
270 | rc = dev->ops->data_exchange(dev, target_idx, skb, cb, cb_context); | |
271 | ||
272 | error: | |
273 | device_unlock(&dev->dev); | |
274 | return rc; | |
275 | } | |
276 | ||
277 | /** | |
278 | * nfc_alloc_skb - allocate a skb for data exchange responses | |
279 | * | |
280 | * @size: size to allocate | |
281 | * @gfp: gfp flags | |
282 | */ | |
283 | struct sk_buff *nfc_alloc_skb(unsigned int size, gfp_t gfp) | |
284 | { | |
285 | struct sk_buff *skb; | |
286 | unsigned int total_size; | |
287 | ||
288 | total_size = size + 1; | |
289 | skb = alloc_skb(total_size, gfp); | |
290 | ||
291 | if (skb) | |
292 | skb_reserve(skb, 1); | |
293 | ||
294 | return skb; | |
295 | } | |
296 | EXPORT_SYMBOL(nfc_alloc_skb); | |
297 | ||
4d12b8b1 LRV |
298 | /** |
299 | * nfc_targets_found - inform that targets were found | |
300 | * | |
301 | * @dev: The nfc device that found the targets | |
302 | * @targets: array of nfc targets found | |
303 | * @ntargets: targets array size | |
304 | * | |
305 | * The device driver must call this function when one or many nfc targets | |
306 | * are found. After calling this function, the device driver must stop | |
307 | * polling for targets. | |
308 | */ | |
309 | int nfc_targets_found(struct nfc_dev *dev, struct nfc_target *targets, | |
310 | int n_targets) | |
311 | { | |
312 | int i; | |
313 | ||
20c239c1 | 314 | pr_debug("dev_name=%s n_targets=%d\n", dev_name(&dev->dev), n_targets); |
4d12b8b1 LRV |
315 | |
316 | dev->polling = false; | |
317 | ||
318 | for (i = 0; i < n_targets; i++) | |
319 | targets[i].idx = dev->target_idx++; | |
320 | ||
321 | spin_lock_bh(&dev->targets_lock); | |
322 | ||
323 | dev->targets_generation++; | |
324 | ||
325 | kfree(dev->targets); | |
326 | dev->targets = kmemdup(targets, n_targets * sizeof(struct nfc_target), | |
327 | GFP_ATOMIC); | |
328 | ||
329 | if (!dev->targets) { | |
330 | dev->n_targets = 0; | |
331 | spin_unlock_bh(&dev->targets_lock); | |
332 | return -ENOMEM; | |
333 | } | |
334 | ||
335 | dev->n_targets = n_targets; | |
336 | spin_unlock_bh(&dev->targets_lock); | |
337 | ||
338 | nfc_genl_targets_found(dev); | |
339 | ||
340 | return 0; | |
341 | } | |
342 | EXPORT_SYMBOL(nfc_targets_found); | |
343 | ||
3e256b8f LRV |
344 | static void nfc_release(struct device *d) |
345 | { | |
346 | struct nfc_dev *dev = to_nfc_dev(d); | |
347 | ||
20c239c1 | 348 | pr_debug("dev_name=%s\n", dev_name(&dev->dev)); |
3e256b8f | 349 | |
4d12b8b1 LRV |
350 | nfc_genl_data_exit(&dev->genl_data); |
351 | kfree(dev->targets); | |
3e256b8f LRV |
352 | kfree(dev); |
353 | } | |
354 | ||
355 | struct class nfc_class = { | |
356 | .name = "nfc", | |
357 | .dev_release = nfc_release, | |
358 | }; | |
359 | EXPORT_SYMBOL(nfc_class); | |
360 | ||
361 | static int match_idx(struct device *d, void *data) | |
362 | { | |
363 | struct nfc_dev *dev = to_nfc_dev(d); | |
364 | unsigned *idx = data; | |
365 | ||
366 | return dev->idx == *idx; | |
367 | } | |
368 | ||
369 | struct nfc_dev *nfc_get_device(unsigned idx) | |
370 | { | |
371 | struct device *d; | |
372 | ||
373 | d = class_find_device(&nfc_class, NULL, &idx, match_idx); | |
374 | if (!d) | |
375 | return NULL; | |
376 | ||
377 | return to_nfc_dev(d); | |
378 | } | |
379 | ||
380 | /** | |
381 | * nfc_allocate_device - allocate a new nfc device | |
382 | * | |
383 | * @ops: device operations | |
384 | * @supported_protocols: NFC protocols supported by the device | |
385 | */ | |
386 | struct nfc_dev *nfc_allocate_device(struct nfc_ops *ops, | |
e8753043 SO |
387 | u32 supported_protocols, |
388 | int tx_headroom, | |
389 | int tx_tailroom) | |
3e256b8f LRV |
390 | { |
391 | static atomic_t dev_no = ATOMIC_INIT(0); | |
392 | struct nfc_dev *dev; | |
393 | ||
394 | if (!ops->start_poll || !ops->stop_poll || !ops->activate_target || | |
395 | !ops->deactivate_target || !ops->data_exchange) | |
396 | return NULL; | |
397 | ||
398 | if (!supported_protocols) | |
399 | return NULL; | |
400 | ||
401 | dev = kzalloc(sizeof(struct nfc_dev), GFP_KERNEL); | |
402 | if (!dev) | |
403 | return NULL; | |
404 | ||
405 | dev->dev.class = &nfc_class; | |
406 | dev->idx = atomic_inc_return(&dev_no) - 1; | |
407 | dev_set_name(&dev->dev, "nfc%d", dev->idx); | |
408 | device_initialize(&dev->dev); | |
409 | ||
410 | dev->ops = ops; | |
411 | dev->supported_protocols = supported_protocols; | |
e8753043 SO |
412 | dev->tx_headroom = tx_headroom; |
413 | dev->tx_tailroom = tx_tailroom; | |
3e256b8f | 414 | |
4d12b8b1 LRV |
415 | spin_lock_init(&dev->targets_lock); |
416 | nfc_genl_data_init(&dev->genl_data); | |
417 | ||
418 | /* first generation must not be 0 */ | |
419 | dev->targets_generation = 1; | |
420 | ||
3e256b8f LRV |
421 | return dev; |
422 | } | |
423 | EXPORT_SYMBOL(nfc_allocate_device); | |
424 | ||
425 | /** | |
426 | * nfc_register_device - register a nfc device in the nfc subsystem | |
427 | * | |
428 | * @dev: The nfc device to register | |
429 | */ | |
430 | int nfc_register_device(struct nfc_dev *dev) | |
431 | { | |
432 | int rc; | |
433 | ||
20c239c1 | 434 | pr_debug("dev_name=%s\n", dev_name(&dev->dev)); |
3e256b8f LRV |
435 | |
436 | mutex_lock(&nfc_devlist_mutex); | |
437 | nfc_devlist_generation++; | |
438 | rc = device_add(&dev->dev); | |
439 | mutex_unlock(&nfc_devlist_mutex); | |
440 | ||
4d12b8b1 LRV |
441 | if (rc < 0) |
442 | return rc; | |
443 | ||
444 | rc = nfc_genl_device_added(dev); | |
445 | if (rc) | |
20c239c1 JP |
446 | pr_debug("The userspace won't be notified that the device %s was added\n", |
447 | dev_name(&dev->dev)); | |
4d12b8b1 LRV |
448 | |
449 | return 0; | |
3e256b8f LRV |
450 | } |
451 | EXPORT_SYMBOL(nfc_register_device); | |
452 | ||
453 | /** | |
454 | * nfc_unregister_device - unregister a nfc device in the nfc subsystem | |
455 | * | |
456 | * @dev: The nfc device to unregister | |
457 | */ | |
458 | void nfc_unregister_device(struct nfc_dev *dev) | |
459 | { | |
4d12b8b1 LRV |
460 | int rc; |
461 | ||
20c239c1 | 462 | pr_debug("dev_name=%s\n", dev_name(&dev->dev)); |
3e256b8f LRV |
463 | |
464 | mutex_lock(&nfc_devlist_mutex); | |
465 | nfc_devlist_generation++; | |
466 | ||
467 | /* lock to avoid unregistering a device while an operation | |
468 | is in progress */ | |
469 | device_lock(&dev->dev); | |
470 | device_del(&dev->dev); | |
471 | device_unlock(&dev->dev); | |
472 | ||
473 | mutex_unlock(&nfc_devlist_mutex); | |
4d12b8b1 LRV |
474 | |
475 | rc = nfc_genl_device_removed(dev); | |
476 | if (rc) | |
20c239c1 JP |
477 | pr_debug("The userspace won't be notified that the device %s was removed\n", |
478 | dev_name(&dev->dev)); | |
4d12b8b1 | 479 | |
3e256b8f LRV |
480 | } |
481 | EXPORT_SYMBOL(nfc_unregister_device); | |
482 | ||
483 | static int __init nfc_init(void) | |
484 | { | |
4d12b8b1 LRV |
485 | int rc; |
486 | ||
ed1e0ad8 | 487 | pr_info("NFC Core ver %s\n", VERSION); |
3e256b8f | 488 | |
4d12b8b1 LRV |
489 | rc = class_register(&nfc_class); |
490 | if (rc) | |
491 | return rc; | |
492 | ||
493 | rc = nfc_genl_init(); | |
494 | if (rc) | |
495 | goto err_genl; | |
496 | ||
497 | /* the first generation must not be 0 */ | |
498 | nfc_devlist_generation = 1; | |
499 | ||
23b7869c LRV |
500 | rc = rawsock_init(); |
501 | if (rc) | |
502 | goto err_rawsock; | |
503 | ||
c7fe3b52 AAJ |
504 | rc = af_nfc_init(); |
505 | if (rc) | |
506 | goto err_af_nfc; | |
507 | ||
4d12b8b1 LRV |
508 | return 0; |
509 | ||
c7fe3b52 | 510 | err_af_nfc: |
23b7869c LRV |
511 | rawsock_exit(); |
512 | err_rawsock: | |
c7fe3b52 | 513 | nfc_genl_exit(); |
4d12b8b1 LRV |
514 | err_genl: |
515 | class_unregister(&nfc_class); | |
516 | return rc; | |
3e256b8f LRV |
517 | } |
518 | ||
519 | static void __exit nfc_exit(void) | |
520 | { | |
c7fe3b52 | 521 | af_nfc_exit(); |
23b7869c | 522 | rawsock_exit(); |
4d12b8b1 | 523 | nfc_genl_exit(); |
3e256b8f LRV |
524 | class_unregister(&nfc_class); |
525 | } | |
526 | ||
527 | subsys_initcall(nfc_init); | |
528 | module_exit(nfc_exit); | |
529 | ||
530 | MODULE_AUTHOR("Lauro Ramos Venancio <lauro.venancio@openbossa.org>"); | |
531 | MODULE_DESCRIPTION("NFC Core ver " VERSION); | |
532 | MODULE_VERSION(VERSION); | |
533 | MODULE_LICENSE("GPL"); |