xref: /linux/net/nfc/digital_core.c (revision f3a8b6645dc2e60d11f20c1c23afd964ff4e55ae)
1 /*
2  * NFC Digital Protocol stack
3  * Copyright (c) 2013, Intel Corporation.
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms and conditions of the GNU General Public License,
7  * version 2, as published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  *
14  */
15 
16 #define pr_fmt(fmt) "digital: %s: " fmt, __func__
17 
18 #include <linux/module.h>
19 
20 #include "digital.h"
21 
22 #define DIGITAL_PROTO_NFCA_RF_TECH \
23 	(NFC_PROTO_JEWEL_MASK | NFC_PROTO_MIFARE_MASK | \
24 	NFC_PROTO_NFC_DEP_MASK | NFC_PROTO_ISO14443_MASK)
25 
26 #define DIGITAL_PROTO_NFCB_RF_TECH	NFC_PROTO_ISO14443_B_MASK
27 
28 #define DIGITAL_PROTO_NFCF_RF_TECH \
29 	(NFC_PROTO_FELICA_MASK | NFC_PROTO_NFC_DEP_MASK)
30 
31 #define DIGITAL_PROTO_ISO15693_RF_TECH	NFC_PROTO_ISO15693_MASK
32 
33 /* Delay between each poll frame (ms) */
34 #define DIGITAL_POLL_INTERVAL 10
35 
36 struct digital_cmd {
37 	struct list_head queue;
38 
39 	u8 type;
40 	u8 pending;
41 
42 	u16 timeout;
43 	struct sk_buff *req;
44 	struct sk_buff *resp;
45 	struct digital_tg_mdaa_params *mdaa_params;
46 
47 	nfc_digital_cmd_complete_t cmd_cb;
48 	void *cb_context;
49 };
50 
51 struct sk_buff *digital_skb_alloc(struct nfc_digital_dev *ddev,
52 				  unsigned int len)
53 {
54 	struct sk_buff *skb;
55 
56 	skb = alloc_skb(len + ddev->tx_headroom + ddev->tx_tailroom,
57 			GFP_KERNEL);
58 	if (skb)
59 		skb_reserve(skb, ddev->tx_headroom);
60 
61 	return skb;
62 }
63 
64 void digital_skb_add_crc(struct sk_buff *skb, crc_func_t crc_func, u16 init,
65 			 u8 bitwise_inv, u8 msb_first)
66 {
67 	u16 crc;
68 
69 	crc = crc_func(init, skb->data, skb->len);
70 
71 	if (bitwise_inv)
72 		crc = ~crc;
73 
74 	if (msb_first)
75 		crc = __fswab16(crc);
76 
77 	*skb_put(skb, 1) = crc & 0xFF;
78 	*skb_put(skb, 1) = (crc >> 8) & 0xFF;
79 }
80 
81 int digital_skb_check_crc(struct sk_buff *skb, crc_func_t crc_func,
82 			  u16 crc_init, u8 bitwise_inv, u8 msb_first)
83 {
84 	int rc;
85 	u16 crc;
86 
87 	if (skb->len <= 2)
88 		return -EIO;
89 
90 	crc = crc_func(crc_init, skb->data, skb->len - 2);
91 
92 	if (bitwise_inv)
93 		crc = ~crc;
94 
95 	if (msb_first)
96 		crc = __swab16(crc);
97 
98 	rc = (skb->data[skb->len - 2] - (crc & 0xFF)) +
99 	     (skb->data[skb->len - 1] - ((crc >> 8) & 0xFF));
100 
101 	if (rc)
102 		return -EIO;
103 
104 	skb_trim(skb, skb->len - 2);
105 
106 	return 0;
107 }
108 
109 static inline void digital_switch_rf(struct nfc_digital_dev *ddev, bool on)
110 {
111 	ddev->ops->switch_rf(ddev, on);
112 }
113 
114 static inline void digital_abort_cmd(struct nfc_digital_dev *ddev)
115 {
116 	ddev->ops->abort_cmd(ddev);
117 }
118 
119 static void digital_wq_cmd_complete(struct work_struct *work)
120 {
121 	struct digital_cmd *cmd;
122 	struct nfc_digital_dev *ddev = container_of(work,
123 						    struct nfc_digital_dev,
124 						    cmd_complete_work);
125 
126 	mutex_lock(&ddev->cmd_lock);
127 
128 	cmd = list_first_entry_or_null(&ddev->cmd_queue, struct digital_cmd,
129 				       queue);
130 	if (!cmd) {
131 		mutex_unlock(&ddev->cmd_lock);
132 		return;
133 	}
134 
135 	list_del(&cmd->queue);
136 
137 	mutex_unlock(&ddev->cmd_lock);
138 
139 	if (!IS_ERR(cmd->resp))
140 		print_hex_dump_debug("DIGITAL RX: ", DUMP_PREFIX_NONE, 16, 1,
141 				     cmd->resp->data, cmd->resp->len, false);
142 
143 	cmd->cmd_cb(ddev, cmd->cb_context, cmd->resp);
144 
145 	kfree(cmd->mdaa_params);
146 	kfree(cmd);
147 
148 	schedule_work(&ddev->cmd_work);
149 }
150 
151 static void digital_send_cmd_complete(struct nfc_digital_dev *ddev,
152 				      void *arg, struct sk_buff *resp)
153 {
154 	struct digital_cmd *cmd = arg;
155 
156 	cmd->resp = resp;
157 
158 	schedule_work(&ddev->cmd_complete_work);
159 }
160 
161 static void digital_wq_cmd(struct work_struct *work)
162 {
163 	int rc;
164 	struct digital_cmd *cmd;
165 	struct digital_tg_mdaa_params *params;
166 	struct nfc_digital_dev *ddev = container_of(work,
167 						    struct nfc_digital_dev,
168 						    cmd_work);
169 
170 	mutex_lock(&ddev->cmd_lock);
171 
172 	cmd = list_first_entry_or_null(&ddev->cmd_queue, struct digital_cmd,
173 				       queue);
174 	if (!cmd || cmd->pending) {
175 		mutex_unlock(&ddev->cmd_lock);
176 		return;
177 	}
178 
179 	cmd->pending = 1;
180 
181 	mutex_unlock(&ddev->cmd_lock);
182 
183 	if (cmd->req)
184 		print_hex_dump_debug("DIGITAL TX: ", DUMP_PREFIX_NONE, 16, 1,
185 				     cmd->req->data, cmd->req->len, false);
186 
187 	switch (cmd->type) {
188 	case DIGITAL_CMD_IN_SEND:
189 		rc = ddev->ops->in_send_cmd(ddev, cmd->req, cmd->timeout,
190 					    digital_send_cmd_complete, cmd);
191 		break;
192 
193 	case DIGITAL_CMD_TG_SEND:
194 		rc = ddev->ops->tg_send_cmd(ddev, cmd->req, cmd->timeout,
195 					    digital_send_cmd_complete, cmd);
196 		break;
197 
198 	case DIGITAL_CMD_TG_LISTEN:
199 		rc = ddev->ops->tg_listen(ddev, cmd->timeout,
200 					  digital_send_cmd_complete, cmd);
201 		break;
202 
203 	case DIGITAL_CMD_TG_LISTEN_MDAA:
204 		params = cmd->mdaa_params;
205 
206 		rc = ddev->ops->tg_listen_mdaa(ddev, params, cmd->timeout,
207 					       digital_send_cmd_complete, cmd);
208 		break;
209 
210 	case DIGITAL_CMD_TG_LISTEN_MD:
211 		rc = ddev->ops->tg_listen_md(ddev, cmd->timeout,
212 					       digital_send_cmd_complete, cmd);
213 		break;
214 
215 	default:
216 		pr_err("Unknown cmd type %d\n", cmd->type);
217 		return;
218 	}
219 
220 	if (!rc)
221 		return;
222 
223 	pr_err("in_send_command returned err %d\n", rc);
224 
225 	mutex_lock(&ddev->cmd_lock);
226 	list_del(&cmd->queue);
227 	mutex_unlock(&ddev->cmd_lock);
228 
229 	kfree_skb(cmd->req);
230 	kfree(cmd->mdaa_params);
231 	kfree(cmd);
232 
233 	schedule_work(&ddev->cmd_work);
234 }
235 
236 int digital_send_cmd(struct nfc_digital_dev *ddev, u8 cmd_type,
237 		     struct sk_buff *skb, struct digital_tg_mdaa_params *params,
238 		     u16 timeout, nfc_digital_cmd_complete_t cmd_cb,
239 		     void *cb_context)
240 {
241 	struct digital_cmd *cmd;
242 
243 	cmd = kzalloc(sizeof(struct digital_cmd), GFP_KERNEL);
244 	if (!cmd)
245 		return -ENOMEM;
246 
247 	cmd->type = cmd_type;
248 	cmd->timeout = timeout;
249 	cmd->req = skb;
250 	cmd->mdaa_params = params;
251 	cmd->cmd_cb = cmd_cb;
252 	cmd->cb_context = cb_context;
253 	INIT_LIST_HEAD(&cmd->queue);
254 
255 	mutex_lock(&ddev->cmd_lock);
256 	list_add_tail(&cmd->queue, &ddev->cmd_queue);
257 	mutex_unlock(&ddev->cmd_lock);
258 
259 	schedule_work(&ddev->cmd_work);
260 
261 	return 0;
262 }
263 
264 int digital_in_configure_hw(struct nfc_digital_dev *ddev, int type, int param)
265 {
266 	int rc;
267 
268 	rc = ddev->ops->in_configure_hw(ddev, type, param);
269 	if (rc)
270 		pr_err("in_configure_hw failed: %d\n", rc);
271 
272 	return rc;
273 }
274 
275 int digital_tg_configure_hw(struct nfc_digital_dev *ddev, int type, int param)
276 {
277 	int rc;
278 
279 	rc = ddev->ops->tg_configure_hw(ddev, type, param);
280 	if (rc)
281 		pr_err("tg_configure_hw failed: %d\n", rc);
282 
283 	return rc;
284 }
285 
286 static int digital_tg_listen_mdaa(struct nfc_digital_dev *ddev, u8 rf_tech)
287 {
288 	struct digital_tg_mdaa_params *params;
289 
290 	params = kzalloc(sizeof(struct digital_tg_mdaa_params), GFP_KERNEL);
291 	if (!params)
292 		return -ENOMEM;
293 
294 	params->sens_res = DIGITAL_SENS_RES_NFC_DEP;
295 	get_random_bytes(params->nfcid1, sizeof(params->nfcid1));
296 	params->sel_res = DIGITAL_SEL_RES_NFC_DEP;
297 
298 	params->nfcid2[0] = DIGITAL_SENSF_NFCID2_NFC_DEP_B1;
299 	params->nfcid2[1] = DIGITAL_SENSF_NFCID2_NFC_DEP_B2;
300 	get_random_bytes(params->nfcid2 + 2, NFC_NFCID2_MAXSIZE - 2);
301 	params->sc = DIGITAL_SENSF_FELICA_SC;
302 
303 	return digital_send_cmd(ddev, DIGITAL_CMD_TG_LISTEN_MDAA, NULL, params,
304 				500, digital_tg_recv_atr_req, NULL);
305 }
306 
307 static int digital_tg_listen_md(struct nfc_digital_dev *ddev, u8 rf_tech)
308 {
309 	return digital_send_cmd(ddev, DIGITAL_CMD_TG_LISTEN_MD, NULL, NULL, 500,
310 				digital_tg_recv_md_req, NULL);
311 }
312 
313 int digital_target_found(struct nfc_digital_dev *ddev,
314 			 struct nfc_target *target, u8 protocol)
315 {
316 	int rc;
317 	u8 framing;
318 	u8 rf_tech;
319 	u8 poll_tech_count;
320 	int (*check_crc)(struct sk_buff *skb);
321 	void (*add_crc)(struct sk_buff *skb);
322 
323 	rf_tech = ddev->poll_techs[ddev->poll_tech_index].rf_tech;
324 
325 	switch (protocol) {
326 	case NFC_PROTO_JEWEL:
327 		framing = NFC_DIGITAL_FRAMING_NFCA_T1T;
328 		check_crc = digital_skb_check_crc_b;
329 		add_crc = digital_skb_add_crc_b;
330 		break;
331 
332 	case NFC_PROTO_MIFARE:
333 		framing = NFC_DIGITAL_FRAMING_NFCA_T2T;
334 		check_crc = digital_skb_check_crc_a;
335 		add_crc = digital_skb_add_crc_a;
336 		break;
337 
338 	case NFC_PROTO_FELICA:
339 		framing = NFC_DIGITAL_FRAMING_NFCF_T3T;
340 		check_crc = digital_skb_check_crc_f;
341 		add_crc = digital_skb_add_crc_f;
342 		break;
343 
344 	case NFC_PROTO_NFC_DEP:
345 		if (rf_tech == NFC_DIGITAL_RF_TECH_106A) {
346 			framing = NFC_DIGITAL_FRAMING_NFCA_NFC_DEP;
347 			check_crc = digital_skb_check_crc_a;
348 			add_crc = digital_skb_add_crc_a;
349 		} else {
350 			framing = NFC_DIGITAL_FRAMING_NFCF_NFC_DEP;
351 			check_crc = digital_skb_check_crc_f;
352 			add_crc = digital_skb_add_crc_f;
353 		}
354 		break;
355 
356 	case NFC_PROTO_ISO15693:
357 		framing = NFC_DIGITAL_FRAMING_ISO15693_T5T;
358 		check_crc = digital_skb_check_crc_b;
359 		add_crc = digital_skb_add_crc_b;
360 		break;
361 
362 	case NFC_PROTO_ISO14443:
363 		framing = NFC_DIGITAL_FRAMING_NFCA_T4T;
364 		check_crc = digital_skb_check_crc_a;
365 		add_crc = digital_skb_add_crc_a;
366 		break;
367 
368 	case NFC_PROTO_ISO14443_B:
369 		framing = NFC_DIGITAL_FRAMING_NFCB_T4T;
370 		check_crc = digital_skb_check_crc_b;
371 		add_crc = digital_skb_add_crc_b;
372 		break;
373 
374 	default:
375 		pr_err("Invalid protocol %d\n", protocol);
376 		return -EINVAL;
377 	}
378 
379 	pr_debug("rf_tech=%d, protocol=%d\n", rf_tech, protocol);
380 
381 	ddev->curr_rf_tech = rf_tech;
382 
383 	if (DIGITAL_DRV_CAPS_IN_CRC(ddev)) {
384 		ddev->skb_add_crc = digital_skb_add_crc_none;
385 		ddev->skb_check_crc = digital_skb_check_crc_none;
386 	} else {
387 		ddev->skb_add_crc = add_crc;
388 		ddev->skb_check_crc = check_crc;
389 	}
390 
391 	rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING, framing);
392 	if (rc)
393 		return rc;
394 
395 	target->supported_protocols = (1 << protocol);
396 
397 	poll_tech_count = ddev->poll_tech_count;
398 	ddev->poll_tech_count = 0;
399 
400 	rc = nfc_targets_found(ddev->nfc_dev, target, 1);
401 	if (rc) {
402 		ddev->poll_tech_count = poll_tech_count;
403 		return rc;
404 	}
405 
406 	return 0;
407 }
408 
409 void digital_poll_next_tech(struct nfc_digital_dev *ddev)
410 {
411 	u8 rand_mod;
412 
413 	digital_switch_rf(ddev, 0);
414 
415 	mutex_lock(&ddev->poll_lock);
416 
417 	if (!ddev->poll_tech_count) {
418 		mutex_unlock(&ddev->poll_lock);
419 		return;
420 	}
421 
422 	get_random_bytes(&rand_mod, sizeof(rand_mod));
423 	ddev->poll_tech_index = rand_mod % ddev->poll_tech_count;
424 
425 	mutex_unlock(&ddev->poll_lock);
426 
427 	schedule_delayed_work(&ddev->poll_work,
428 			      msecs_to_jiffies(DIGITAL_POLL_INTERVAL));
429 }
430 
431 static void digital_wq_poll(struct work_struct *work)
432 {
433 	int rc;
434 	struct digital_poll_tech *poll_tech;
435 	struct nfc_digital_dev *ddev = container_of(work,
436 						    struct nfc_digital_dev,
437 						    poll_work.work);
438 	mutex_lock(&ddev->poll_lock);
439 
440 	if (!ddev->poll_tech_count) {
441 		mutex_unlock(&ddev->poll_lock);
442 		return;
443 	}
444 
445 	poll_tech = &ddev->poll_techs[ddev->poll_tech_index];
446 
447 	mutex_unlock(&ddev->poll_lock);
448 
449 	rc = poll_tech->poll_func(ddev, poll_tech->rf_tech);
450 	if (rc)
451 		digital_poll_next_tech(ddev);
452 }
453 
454 static void digital_add_poll_tech(struct nfc_digital_dev *ddev, u8 rf_tech,
455 				  digital_poll_t poll_func)
456 {
457 	struct digital_poll_tech *poll_tech;
458 
459 	if (ddev->poll_tech_count >= NFC_DIGITAL_POLL_MODE_COUNT_MAX)
460 		return;
461 
462 	poll_tech = &ddev->poll_techs[ddev->poll_tech_count++];
463 
464 	poll_tech->rf_tech = rf_tech;
465 	poll_tech->poll_func = poll_func;
466 }
467 
468 /**
469  * start_poll operation
470  *
471  * For every supported protocol, the corresponding polling function is added
472  * to the table of polling technologies (ddev->poll_techs[]) using
473  * digital_add_poll_tech().
474  * When a polling function fails (by timeout or protocol error) the next one is
475  * schedule by digital_poll_next_tech() on the poll workqueue (ddev->poll_work).
476  */
477 static int digital_start_poll(struct nfc_dev *nfc_dev, __u32 im_protocols,
478 			      __u32 tm_protocols)
479 {
480 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
481 	u32 matching_im_protocols, matching_tm_protocols;
482 
483 	pr_debug("protocols: im 0x%x, tm 0x%x, supported 0x%x\n", im_protocols,
484 		 tm_protocols, ddev->protocols);
485 
486 	matching_im_protocols = ddev->protocols & im_protocols;
487 	matching_tm_protocols = ddev->protocols & tm_protocols;
488 
489 	if (!matching_im_protocols && !matching_tm_protocols) {
490 		pr_err("Unknown protocol\n");
491 		return -EINVAL;
492 	}
493 
494 	if (ddev->poll_tech_count) {
495 		pr_err("Already polling\n");
496 		return -EBUSY;
497 	}
498 
499 	if (ddev->curr_protocol) {
500 		pr_err("A target is already active\n");
501 		return -EBUSY;
502 	}
503 
504 	ddev->poll_tech_count = 0;
505 	ddev->poll_tech_index = 0;
506 
507 	if (matching_im_protocols & DIGITAL_PROTO_NFCA_RF_TECH)
508 		digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_106A,
509 				      digital_in_send_sens_req);
510 
511 	if (matching_im_protocols & DIGITAL_PROTO_NFCB_RF_TECH)
512 		digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_106B,
513 				      digital_in_send_sensb_req);
514 
515 	if (matching_im_protocols & DIGITAL_PROTO_NFCF_RF_TECH) {
516 		digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_212F,
517 				      digital_in_send_sensf_req);
518 
519 		digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_424F,
520 				      digital_in_send_sensf_req);
521 	}
522 
523 	if (matching_im_protocols & DIGITAL_PROTO_ISO15693_RF_TECH)
524 		digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_ISO15693,
525 				      digital_in_send_iso15693_inv_req);
526 
527 	if (matching_tm_protocols & NFC_PROTO_NFC_DEP_MASK) {
528 		if (ddev->ops->tg_listen_mdaa) {
529 			digital_add_poll_tech(ddev, 0,
530 					      digital_tg_listen_mdaa);
531 		} else if (ddev->ops->tg_listen_md) {
532 			digital_add_poll_tech(ddev, 0,
533 					      digital_tg_listen_md);
534 		} else {
535 			digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_106A,
536 					      digital_tg_listen_nfca);
537 
538 			digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_212F,
539 					      digital_tg_listen_nfcf);
540 
541 			digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_424F,
542 					      digital_tg_listen_nfcf);
543 		}
544 	}
545 
546 	if (!ddev->poll_tech_count) {
547 		pr_err("Unsupported protocols: im=0x%x, tm=0x%x\n",
548 		       matching_im_protocols, matching_tm_protocols);
549 		return -EINVAL;
550 	}
551 
552 	schedule_delayed_work(&ddev->poll_work, 0);
553 
554 	return 0;
555 }
556 
557 static void digital_stop_poll(struct nfc_dev *nfc_dev)
558 {
559 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
560 
561 	mutex_lock(&ddev->poll_lock);
562 
563 	if (!ddev->poll_tech_count) {
564 		pr_err("Polling operation was not running\n");
565 		mutex_unlock(&ddev->poll_lock);
566 		return;
567 	}
568 
569 	ddev->poll_tech_count = 0;
570 
571 	mutex_unlock(&ddev->poll_lock);
572 
573 	cancel_delayed_work_sync(&ddev->poll_work);
574 
575 	digital_abort_cmd(ddev);
576 }
577 
578 static int digital_dev_up(struct nfc_dev *nfc_dev)
579 {
580 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
581 
582 	digital_switch_rf(ddev, 1);
583 
584 	return 0;
585 }
586 
587 static int digital_dev_down(struct nfc_dev *nfc_dev)
588 {
589 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
590 
591 	digital_switch_rf(ddev, 0);
592 
593 	return 0;
594 }
595 
596 static int digital_dep_link_up(struct nfc_dev *nfc_dev,
597 			       struct nfc_target *target,
598 			       __u8 comm_mode, __u8 *gb, size_t gb_len)
599 {
600 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
601 	int rc;
602 
603 	rc = digital_in_send_atr_req(ddev, target, comm_mode, gb, gb_len);
604 
605 	if (!rc)
606 		ddev->curr_protocol = NFC_PROTO_NFC_DEP;
607 
608 	return rc;
609 }
610 
611 static int digital_dep_link_down(struct nfc_dev *nfc_dev)
612 {
613 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
614 
615 	digital_abort_cmd(ddev);
616 
617 	ddev->curr_protocol = 0;
618 
619 	return 0;
620 }
621 
622 static int digital_activate_target(struct nfc_dev *nfc_dev,
623 				   struct nfc_target *target, __u32 protocol)
624 {
625 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
626 
627 	if (ddev->poll_tech_count) {
628 		pr_err("Can't activate a target while polling\n");
629 		return -EBUSY;
630 	}
631 
632 	if (ddev->curr_protocol) {
633 		pr_err("A target is already active\n");
634 		return -EBUSY;
635 	}
636 
637 	ddev->curr_protocol = protocol;
638 
639 	return 0;
640 }
641 
642 static void digital_deactivate_target(struct nfc_dev *nfc_dev,
643 				      struct nfc_target *target,
644 				      u8 mode)
645 {
646 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
647 
648 	if (!ddev->curr_protocol) {
649 		pr_err("No active target\n");
650 		return;
651 	}
652 
653 	ddev->curr_protocol = 0;
654 }
655 
656 static int digital_tg_send(struct nfc_dev *dev, struct sk_buff *skb)
657 {
658 	struct nfc_digital_dev *ddev = nfc_get_drvdata(dev);
659 
660 	return digital_tg_send_dep_res(ddev, skb);
661 }
662 
663 static void digital_in_send_complete(struct nfc_digital_dev *ddev, void *arg,
664 				     struct sk_buff *resp)
665 {
666 	struct digital_data_exch *data_exch = arg;
667 	int rc;
668 
669 	if (IS_ERR(resp)) {
670 		rc = PTR_ERR(resp);
671 		resp = NULL;
672 		goto done;
673 	}
674 
675 	if (ddev->curr_protocol == NFC_PROTO_MIFARE) {
676 		rc = digital_in_recv_mifare_res(resp);
677 		/* crc check is done in digital_in_recv_mifare_res() */
678 		goto done;
679 	}
680 
681 	if ((ddev->curr_protocol == NFC_PROTO_ISO14443) ||
682 	    (ddev->curr_protocol == NFC_PROTO_ISO14443_B)) {
683 		rc = digital_in_iso_dep_pull_sod(ddev, resp);
684 		if (rc)
685 			goto done;
686 	}
687 
688 	rc = ddev->skb_check_crc(resp);
689 
690 done:
691 	if (rc) {
692 		kfree_skb(resp);
693 		resp = NULL;
694 	}
695 
696 	data_exch->cb(data_exch->cb_context, resp, rc);
697 
698 	kfree(data_exch);
699 }
700 
701 static int digital_in_send(struct nfc_dev *nfc_dev, struct nfc_target *target,
702 			   struct sk_buff *skb, data_exchange_cb_t cb,
703 			   void *cb_context)
704 {
705 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
706 	struct digital_data_exch *data_exch;
707 	int rc;
708 
709 	data_exch = kzalloc(sizeof(struct digital_data_exch), GFP_KERNEL);
710 	if (!data_exch) {
711 		pr_err("Failed to allocate data_exch struct\n");
712 		return -ENOMEM;
713 	}
714 
715 	data_exch->cb = cb;
716 	data_exch->cb_context = cb_context;
717 
718 	if (ddev->curr_protocol == NFC_PROTO_NFC_DEP) {
719 		rc = digital_in_send_dep_req(ddev, target, skb, data_exch);
720 		goto exit;
721 	}
722 
723 	if ((ddev->curr_protocol == NFC_PROTO_ISO14443) ||
724 	    (ddev->curr_protocol == NFC_PROTO_ISO14443_B)) {
725 		rc = digital_in_iso_dep_push_sod(ddev, skb);
726 		if (rc)
727 			goto exit;
728 	}
729 
730 	ddev->skb_add_crc(skb);
731 
732 	rc = digital_in_send_cmd(ddev, skb, 500, digital_in_send_complete,
733 				 data_exch);
734 
735 exit:
736 	if (rc)
737 		kfree(data_exch);
738 
739 	return rc;
740 }
741 
742 static struct nfc_ops digital_nfc_ops = {
743 	.dev_up = digital_dev_up,
744 	.dev_down = digital_dev_down,
745 	.start_poll = digital_start_poll,
746 	.stop_poll = digital_stop_poll,
747 	.dep_link_up = digital_dep_link_up,
748 	.dep_link_down = digital_dep_link_down,
749 	.activate_target = digital_activate_target,
750 	.deactivate_target = digital_deactivate_target,
751 	.tm_send = digital_tg_send,
752 	.im_transceive = digital_in_send,
753 };
754 
755 struct nfc_digital_dev *nfc_digital_allocate_device(struct nfc_digital_ops *ops,
756 					    __u32 supported_protocols,
757 					    __u32 driver_capabilities,
758 					    int tx_headroom, int tx_tailroom)
759 {
760 	struct nfc_digital_dev *ddev;
761 
762 	if (!ops->in_configure_hw || !ops->in_send_cmd || !ops->tg_listen ||
763 	    !ops->tg_configure_hw || !ops->tg_send_cmd || !ops->abort_cmd ||
764 	    !ops->switch_rf || (ops->tg_listen_md && !ops->tg_get_rf_tech))
765 		return NULL;
766 
767 	ddev = kzalloc(sizeof(struct nfc_digital_dev), GFP_KERNEL);
768 	if (!ddev)
769 		return NULL;
770 
771 	ddev->driver_capabilities = driver_capabilities;
772 	ddev->ops = ops;
773 
774 	mutex_init(&ddev->cmd_lock);
775 	INIT_LIST_HEAD(&ddev->cmd_queue);
776 
777 	INIT_WORK(&ddev->cmd_work, digital_wq_cmd);
778 	INIT_WORK(&ddev->cmd_complete_work, digital_wq_cmd_complete);
779 
780 	mutex_init(&ddev->poll_lock);
781 	INIT_DELAYED_WORK(&ddev->poll_work, digital_wq_poll);
782 
783 	if (supported_protocols & NFC_PROTO_JEWEL_MASK)
784 		ddev->protocols |= NFC_PROTO_JEWEL_MASK;
785 	if (supported_protocols & NFC_PROTO_MIFARE_MASK)
786 		ddev->protocols |= NFC_PROTO_MIFARE_MASK;
787 	if (supported_protocols & NFC_PROTO_FELICA_MASK)
788 		ddev->protocols |= NFC_PROTO_FELICA_MASK;
789 	if (supported_protocols & NFC_PROTO_NFC_DEP_MASK)
790 		ddev->protocols |= NFC_PROTO_NFC_DEP_MASK;
791 	if (supported_protocols & NFC_PROTO_ISO15693_MASK)
792 		ddev->protocols |= NFC_PROTO_ISO15693_MASK;
793 	if (supported_protocols & NFC_PROTO_ISO14443_MASK)
794 		ddev->protocols |= NFC_PROTO_ISO14443_MASK;
795 	if (supported_protocols & NFC_PROTO_ISO14443_B_MASK)
796 		ddev->protocols |= NFC_PROTO_ISO14443_B_MASK;
797 
798 	ddev->tx_headroom = tx_headroom + DIGITAL_MAX_HEADER_LEN;
799 	ddev->tx_tailroom = tx_tailroom + DIGITAL_CRC_LEN;
800 
801 	ddev->nfc_dev = nfc_allocate_device(&digital_nfc_ops, ddev->protocols,
802 					    ddev->tx_headroom,
803 					    ddev->tx_tailroom);
804 	if (!ddev->nfc_dev) {
805 		pr_err("nfc_allocate_device failed\n");
806 		goto free_dev;
807 	}
808 
809 	nfc_set_drvdata(ddev->nfc_dev, ddev);
810 
811 	return ddev;
812 
813 free_dev:
814 	kfree(ddev);
815 
816 	return NULL;
817 }
818 EXPORT_SYMBOL(nfc_digital_allocate_device);
819 
820 void nfc_digital_free_device(struct nfc_digital_dev *ddev)
821 {
822 	nfc_free_device(ddev->nfc_dev);
823 	kfree(ddev);
824 }
825 EXPORT_SYMBOL(nfc_digital_free_device);
826 
827 int nfc_digital_register_device(struct nfc_digital_dev *ddev)
828 {
829 	return nfc_register_device(ddev->nfc_dev);
830 }
831 EXPORT_SYMBOL(nfc_digital_register_device);
832 
833 void nfc_digital_unregister_device(struct nfc_digital_dev *ddev)
834 {
835 	struct digital_cmd *cmd, *n;
836 
837 	nfc_unregister_device(ddev->nfc_dev);
838 
839 	mutex_lock(&ddev->poll_lock);
840 	ddev->poll_tech_count = 0;
841 	mutex_unlock(&ddev->poll_lock);
842 
843 	cancel_delayed_work_sync(&ddev->poll_work);
844 	cancel_work_sync(&ddev->cmd_work);
845 	cancel_work_sync(&ddev->cmd_complete_work);
846 
847 	list_for_each_entry_safe(cmd, n, &ddev->cmd_queue, queue) {
848 		list_del(&cmd->queue);
849 
850 		/* Call the command callback if any and pass it a ENODEV error.
851 		 * This gives a chance to the command issuer to free any
852 		 * allocated buffer.
853 		 */
854 		if (cmd->cmd_cb)
855 			cmd->cmd_cb(ddev, cmd->cb_context, ERR_PTR(-ENODEV));
856 
857 		kfree(cmd->mdaa_params);
858 		kfree(cmd);
859 	}
860 }
861 EXPORT_SYMBOL(nfc_digital_unregister_device);
862 
863 MODULE_LICENSE("GPL");
864