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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 | ||
24 | #include <linux/init.h> | |
25 | #include <linux/kernel.h> | |
26 | #include <linux/module.h> | |
27 | #include <linux/slab.h> | |
28 | ||
29 | #include "nfc.h" | |
30 | ||
31 | #define VERSION "0.1" | |
32 | ||
33 | int nfc_devlist_generation; | |
34 | DEFINE_MUTEX(nfc_devlist_mutex); | |
35 | ||
36 | int nfc_printk(const char *level, const char *format, ...) | |
37 | { | |
38 | struct va_format vaf; | |
39 | va_list args; | |
40 | int r; | |
41 | ||
42 | va_start(args, format); | |
43 | ||
44 | vaf.fmt = format; | |
45 | vaf.va = &args; | |
46 | ||
47 | r = printk("%sNFC: %pV\n", level, &vaf); | |
48 | ||
49 | va_end(args); | |
50 | ||
51 | return r; | |
52 | } | |
53 | EXPORT_SYMBOL(nfc_printk); | |
54 | ||
8b3fe7b5 IE |
55 | /** |
56 | * nfc_dev_up - turn on the NFC device | |
57 | * | |
58 | * @dev: The nfc device to be turned on | |
59 | * | |
60 | * The device remains up until the nfc_dev_down function is called. | |
61 | */ | |
62 | int nfc_dev_up(struct nfc_dev *dev) | |
63 | { | |
64 | int rc = 0; | |
65 | ||
66 | nfc_dbg("dev_name=%s", dev_name(&dev->dev)); | |
67 | ||
68 | device_lock(&dev->dev); | |
69 | ||
70 | if (!device_is_registered(&dev->dev)) { | |
71 | rc = -ENODEV; | |
72 | goto error; | |
73 | } | |
74 | ||
75 | if (dev->dev_up) { | |
76 | rc = -EALREADY; | |
77 | goto error; | |
78 | } | |
79 | ||
80 | if (dev->ops->dev_up) | |
81 | rc = dev->ops->dev_up(dev); | |
82 | ||
83 | if (!rc) | |
84 | dev->dev_up = true; | |
85 | ||
86 | error: | |
87 | device_unlock(&dev->dev); | |
88 | return rc; | |
89 | } | |
90 | ||
91 | /** | |
92 | * nfc_dev_down - turn off the NFC device | |
93 | * | |
94 | * @dev: The nfc device to be turned off | |
95 | */ | |
96 | int nfc_dev_down(struct nfc_dev *dev) | |
97 | { | |
98 | int rc = 0; | |
99 | ||
100 | nfc_dbg("dev_name=%s", dev_name(&dev->dev)); | |
101 | ||
102 | device_lock(&dev->dev); | |
103 | ||
104 | if (!device_is_registered(&dev->dev)) { | |
105 | rc = -ENODEV; | |
106 | goto error; | |
107 | } | |
108 | ||
109 | if (!dev->dev_up) { | |
110 | rc = -EALREADY; | |
111 | goto error; | |
112 | } | |
113 | ||
114 | if (dev->polling || dev->remote_activated) { | |
115 | rc = -EBUSY; | |
116 | goto error; | |
117 | } | |
118 | ||
119 | if (dev->ops->dev_down) | |
120 | dev->ops->dev_down(dev); | |
121 | ||
122 | dev->dev_up = false; | |
123 | ||
124 | error: | |
125 | device_unlock(&dev->dev); | |
126 | return rc; | |
127 | } | |
128 | ||
3e256b8f LRV |
129 | /** |
130 | * nfc_start_poll - start polling for nfc targets | |
131 | * | |
132 | * @dev: The nfc device that must start polling | |
133 | * @protocols: bitset of nfc protocols that must be used for polling | |
134 | * | |
135 | * The device remains polling for targets until a target is found or | |
136 | * the nfc_stop_poll function is called. | |
137 | */ | |
138 | int nfc_start_poll(struct nfc_dev *dev, u32 protocols) | |
139 | { | |
140 | int rc; | |
141 | ||
142 | nfc_dbg("dev_name=%s protocols=0x%x", dev_name(&dev->dev), protocols); | |
143 | ||
144 | if (!protocols) | |
145 | return -EINVAL; | |
146 | ||
147 | device_lock(&dev->dev); | |
148 | ||
149 | if (!device_is_registered(&dev->dev)) { | |
150 | rc = -ENODEV; | |
151 | goto error; | |
152 | } | |
153 | ||
154 | if (dev->polling) { | |
155 | rc = -EBUSY; | |
156 | goto error; | |
157 | } | |
158 | ||
159 | rc = dev->ops->start_poll(dev, protocols); | |
160 | if (!rc) | |
161 | dev->polling = true; | |
162 | ||
163 | error: | |
164 | device_unlock(&dev->dev); | |
165 | return rc; | |
166 | } | |
167 | ||
168 | /** | |
169 | * nfc_stop_poll - stop polling for nfc targets | |
170 | * | |
171 | * @dev: The nfc device that must stop polling | |
172 | */ | |
173 | int nfc_stop_poll(struct nfc_dev *dev) | |
174 | { | |
175 | int rc = 0; | |
176 | ||
177 | nfc_dbg("dev_name=%s", dev_name(&dev->dev)); | |
178 | ||
179 | device_lock(&dev->dev); | |
180 | ||
181 | if (!device_is_registered(&dev->dev)) { | |
182 | rc = -ENODEV; | |
183 | goto error; | |
184 | } | |
185 | ||
186 | if (!dev->polling) { | |
187 | rc = -EINVAL; | |
188 | goto error; | |
189 | } | |
190 | ||
191 | dev->ops->stop_poll(dev); | |
192 | dev->polling = false; | |
193 | ||
194 | error: | |
195 | device_unlock(&dev->dev); | |
196 | return rc; | |
197 | } | |
198 | ||
199 | /** | |
200 | * nfc_activate_target - prepare the target for data exchange | |
201 | * | |
202 | * @dev: The nfc device that found the target | |
203 | * @target_idx: index of the target that must be activated | |
204 | * @protocol: nfc protocol that will be used for data exchange | |
205 | */ | |
206 | int nfc_activate_target(struct nfc_dev *dev, u32 target_idx, u32 protocol) | |
207 | { | |
208 | int rc; | |
209 | ||
210 | nfc_dbg("dev_name=%s target_idx=%u protocol=%u", dev_name(&dev->dev), | |
211 | target_idx, protocol); | |
212 | ||
213 | device_lock(&dev->dev); | |
214 | ||
215 | if (!device_is_registered(&dev->dev)) { | |
216 | rc = -ENODEV; | |
217 | goto error; | |
218 | } | |
219 | ||
220 | rc = dev->ops->activate_target(dev, target_idx, protocol); | |
8b3fe7b5 IE |
221 | if (!rc) |
222 | dev->remote_activated = true; | |
3e256b8f LRV |
223 | |
224 | error: | |
225 | device_unlock(&dev->dev); | |
226 | return rc; | |
227 | } | |
228 | ||
229 | /** | |
230 | * nfc_deactivate_target - deactivate a nfc target | |
231 | * | |
232 | * @dev: The nfc device that found the target | |
233 | * @target_idx: index of the target that must be deactivated | |
234 | */ | |
235 | int nfc_deactivate_target(struct nfc_dev *dev, u32 target_idx) | |
236 | { | |
237 | int rc = 0; | |
238 | ||
239 | nfc_dbg("dev_name=%s target_idx=%u", dev_name(&dev->dev), target_idx); | |
240 | ||
241 | device_lock(&dev->dev); | |
242 | ||
243 | if (!device_is_registered(&dev->dev)) { | |
244 | rc = -ENODEV; | |
245 | goto error; | |
246 | } | |
247 | ||
248 | dev->ops->deactivate_target(dev, target_idx); | |
8b3fe7b5 | 249 | dev->remote_activated = false; |
3e256b8f LRV |
250 | |
251 | error: | |
252 | device_unlock(&dev->dev); | |
253 | return rc; | |
254 | } | |
255 | ||
256 | /** | |
257 | * nfc_data_exchange - transceive data | |
258 | * | |
259 | * @dev: The nfc device that found the target | |
260 | * @target_idx: index of the target | |
261 | * @skb: data to be sent | |
262 | * @cb: callback called when the response is received | |
263 | * @cb_context: parameter for the callback function | |
264 | * | |
265 | * The user must wait for the callback before calling this function again. | |
266 | */ | |
267 | int nfc_data_exchange(struct nfc_dev *dev, u32 target_idx, | |
268 | struct sk_buff *skb, | |
269 | data_exchange_cb_t cb, | |
270 | void *cb_context) | |
271 | { | |
272 | int rc; | |
273 | ||
274 | nfc_dbg("dev_name=%s target_idx=%u skb->len=%u", dev_name(&dev->dev), | |
275 | target_idx, skb->len); | |
276 | ||
277 | device_lock(&dev->dev); | |
278 | ||
279 | if (!device_is_registered(&dev->dev)) { | |
280 | rc = -ENODEV; | |
281 | kfree_skb(skb); | |
282 | goto error; | |
283 | } | |
284 | ||
285 | rc = dev->ops->data_exchange(dev, target_idx, skb, cb, cb_context); | |
286 | ||
287 | error: | |
288 | device_unlock(&dev->dev); | |
289 | return rc; | |
290 | } | |
291 | ||
292 | /** | |
293 | * nfc_alloc_skb - allocate a skb for data exchange responses | |
294 | * | |
295 | * @size: size to allocate | |
296 | * @gfp: gfp flags | |
297 | */ | |
298 | struct sk_buff *nfc_alloc_skb(unsigned int size, gfp_t gfp) | |
299 | { | |
300 | struct sk_buff *skb; | |
301 | unsigned int total_size; | |
302 | ||
303 | total_size = size + 1; | |
304 | skb = alloc_skb(total_size, gfp); | |
305 | ||
306 | if (skb) | |
307 | skb_reserve(skb, 1); | |
308 | ||
309 | return skb; | |
310 | } | |
311 | EXPORT_SYMBOL(nfc_alloc_skb); | |
312 | ||
4d12b8b1 LRV |
313 | /** |
314 | * nfc_targets_found - inform that targets were found | |
315 | * | |
316 | * @dev: The nfc device that found the targets | |
317 | * @targets: array of nfc targets found | |
318 | * @ntargets: targets array size | |
319 | * | |
320 | * The device driver must call this function when one or many nfc targets | |
321 | * are found. After calling this function, the device driver must stop | |
322 | * polling for targets. | |
323 | */ | |
324 | int nfc_targets_found(struct nfc_dev *dev, struct nfc_target *targets, | |
325 | int n_targets) | |
326 | { | |
327 | int i; | |
328 | ||
329 | nfc_dbg("dev_name=%s n_targets=%d", dev_name(&dev->dev), n_targets); | |
330 | ||
331 | dev->polling = false; | |
332 | ||
333 | for (i = 0; i < n_targets; i++) | |
334 | targets[i].idx = dev->target_idx++; | |
335 | ||
336 | spin_lock_bh(&dev->targets_lock); | |
337 | ||
338 | dev->targets_generation++; | |
339 | ||
340 | kfree(dev->targets); | |
341 | dev->targets = kmemdup(targets, n_targets * sizeof(struct nfc_target), | |
342 | GFP_ATOMIC); | |
343 | ||
344 | if (!dev->targets) { | |
345 | dev->n_targets = 0; | |
346 | spin_unlock_bh(&dev->targets_lock); | |
347 | return -ENOMEM; | |
348 | } | |
349 | ||
350 | dev->n_targets = n_targets; | |
351 | spin_unlock_bh(&dev->targets_lock); | |
352 | ||
353 | nfc_genl_targets_found(dev); | |
354 | ||
355 | return 0; | |
356 | } | |
357 | EXPORT_SYMBOL(nfc_targets_found); | |
358 | ||
3e256b8f LRV |
359 | static void nfc_release(struct device *d) |
360 | { | |
361 | struct nfc_dev *dev = to_nfc_dev(d); | |
362 | ||
363 | nfc_dbg("dev_name=%s", dev_name(&dev->dev)); | |
364 | ||
4d12b8b1 LRV |
365 | nfc_genl_data_exit(&dev->genl_data); |
366 | kfree(dev->targets); | |
3e256b8f LRV |
367 | kfree(dev); |
368 | } | |
369 | ||
370 | struct class nfc_class = { | |
371 | .name = "nfc", | |
372 | .dev_release = nfc_release, | |
373 | }; | |
374 | EXPORT_SYMBOL(nfc_class); | |
375 | ||
376 | static int match_idx(struct device *d, void *data) | |
377 | { | |
378 | struct nfc_dev *dev = to_nfc_dev(d); | |
379 | unsigned *idx = data; | |
380 | ||
381 | return dev->idx == *idx; | |
382 | } | |
383 | ||
384 | struct nfc_dev *nfc_get_device(unsigned idx) | |
385 | { | |
386 | struct device *d; | |
387 | ||
388 | d = class_find_device(&nfc_class, NULL, &idx, match_idx); | |
389 | if (!d) | |
390 | return NULL; | |
391 | ||
392 | return to_nfc_dev(d); | |
393 | } | |
394 | ||
395 | /** | |
396 | * nfc_allocate_device - allocate a new nfc device | |
397 | * | |
398 | * @ops: device operations | |
399 | * @supported_protocols: NFC protocols supported by the device | |
400 | */ | |
401 | struct nfc_dev *nfc_allocate_device(struct nfc_ops *ops, | |
e8753043 SO |
402 | u32 supported_protocols, |
403 | int tx_headroom, | |
404 | int tx_tailroom) | |
3e256b8f LRV |
405 | { |
406 | static atomic_t dev_no = ATOMIC_INIT(0); | |
407 | struct nfc_dev *dev; | |
408 | ||
409 | if (!ops->start_poll || !ops->stop_poll || !ops->activate_target || | |
410 | !ops->deactivate_target || !ops->data_exchange) | |
411 | return NULL; | |
412 | ||
413 | if (!supported_protocols) | |
414 | return NULL; | |
415 | ||
416 | dev = kzalloc(sizeof(struct nfc_dev), GFP_KERNEL); | |
417 | if (!dev) | |
418 | return NULL; | |
419 | ||
420 | dev->dev.class = &nfc_class; | |
421 | dev->idx = atomic_inc_return(&dev_no) - 1; | |
422 | dev_set_name(&dev->dev, "nfc%d", dev->idx); | |
423 | device_initialize(&dev->dev); | |
424 | ||
425 | dev->ops = ops; | |
426 | dev->supported_protocols = supported_protocols; | |
e8753043 SO |
427 | dev->tx_headroom = tx_headroom; |
428 | dev->tx_tailroom = tx_tailroom; | |
3e256b8f | 429 | |
4d12b8b1 LRV |
430 | spin_lock_init(&dev->targets_lock); |
431 | nfc_genl_data_init(&dev->genl_data); | |
432 | ||
433 | /* first generation must not be 0 */ | |
434 | dev->targets_generation = 1; | |
435 | ||
3e256b8f LRV |
436 | return dev; |
437 | } | |
438 | EXPORT_SYMBOL(nfc_allocate_device); | |
439 | ||
440 | /** | |
441 | * nfc_register_device - register a nfc device in the nfc subsystem | |
442 | * | |
443 | * @dev: The nfc device to register | |
444 | */ | |
445 | int nfc_register_device(struct nfc_dev *dev) | |
446 | { | |
447 | int rc; | |
448 | ||
449 | nfc_dbg("dev_name=%s", dev_name(&dev->dev)); | |
450 | ||
451 | mutex_lock(&nfc_devlist_mutex); | |
452 | nfc_devlist_generation++; | |
453 | rc = device_add(&dev->dev); | |
454 | mutex_unlock(&nfc_devlist_mutex); | |
455 | ||
4d12b8b1 LRV |
456 | if (rc < 0) |
457 | return rc; | |
458 | ||
459 | rc = nfc_genl_device_added(dev); | |
460 | if (rc) | |
461 | nfc_dbg("The userspace won't be notified that the device %s was" | |
462 | " added", dev_name(&dev->dev)); | |
463 | ||
464 | ||
465 | return 0; | |
3e256b8f LRV |
466 | } |
467 | EXPORT_SYMBOL(nfc_register_device); | |
468 | ||
469 | /** | |
470 | * nfc_unregister_device - unregister a nfc device in the nfc subsystem | |
471 | * | |
472 | * @dev: The nfc device to unregister | |
473 | */ | |
474 | void nfc_unregister_device(struct nfc_dev *dev) | |
475 | { | |
4d12b8b1 LRV |
476 | int rc; |
477 | ||
3e256b8f LRV |
478 | nfc_dbg("dev_name=%s", dev_name(&dev->dev)); |
479 | ||
480 | mutex_lock(&nfc_devlist_mutex); | |
481 | nfc_devlist_generation++; | |
482 | ||
483 | /* lock to avoid unregistering a device while an operation | |
484 | is in progress */ | |
485 | device_lock(&dev->dev); | |
486 | device_del(&dev->dev); | |
487 | device_unlock(&dev->dev); | |
488 | ||
489 | mutex_unlock(&nfc_devlist_mutex); | |
4d12b8b1 LRV |
490 | |
491 | rc = nfc_genl_device_removed(dev); | |
492 | if (rc) | |
493 | nfc_dbg("The userspace won't be notified that the device %s" | |
494 | " was removed", dev_name(&dev->dev)); | |
495 | ||
3e256b8f LRV |
496 | } |
497 | EXPORT_SYMBOL(nfc_unregister_device); | |
498 | ||
499 | static int __init nfc_init(void) | |
500 | { | |
4d12b8b1 LRV |
501 | int rc; |
502 | ||
3e256b8f LRV |
503 | nfc_info("NFC Core ver %s", VERSION); |
504 | ||
4d12b8b1 LRV |
505 | rc = class_register(&nfc_class); |
506 | if (rc) | |
507 | return rc; | |
508 | ||
509 | rc = nfc_genl_init(); | |
510 | if (rc) | |
511 | goto err_genl; | |
512 | ||
513 | /* the first generation must not be 0 */ | |
514 | nfc_devlist_generation = 1; | |
515 | ||
23b7869c LRV |
516 | rc = rawsock_init(); |
517 | if (rc) | |
518 | goto err_rawsock; | |
519 | ||
c7fe3b52 AAJ |
520 | rc = af_nfc_init(); |
521 | if (rc) | |
522 | goto err_af_nfc; | |
523 | ||
4d12b8b1 LRV |
524 | return 0; |
525 | ||
c7fe3b52 | 526 | err_af_nfc: |
23b7869c LRV |
527 | rawsock_exit(); |
528 | err_rawsock: | |
c7fe3b52 | 529 | nfc_genl_exit(); |
4d12b8b1 LRV |
530 | err_genl: |
531 | class_unregister(&nfc_class); | |
532 | return rc; | |
3e256b8f LRV |
533 | } |
534 | ||
535 | static void __exit nfc_exit(void) | |
536 | { | |
c7fe3b52 | 537 | af_nfc_exit(); |
23b7869c | 538 | rawsock_exit(); |
4d12b8b1 | 539 | nfc_genl_exit(); |
3e256b8f LRV |
540 | class_unregister(&nfc_class); |
541 | } | |
542 | ||
543 | subsys_initcall(nfc_init); | |
544 | module_exit(nfc_exit); | |
545 | ||
546 | MODULE_AUTHOR("Lauro Ramos Venancio <lauro.venancio@openbossa.org>"); | |
547 | MODULE_DESCRIPTION("NFC Core ver " VERSION); | |
548 | MODULE_VERSION(VERSION); | |
549 | MODULE_LICENSE("GPL"); |