xref: /linux/net/nfc/digital_core.c (revision 56d06fa29edd58c448766014afd833b7ff51247b)
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 struct digital_cmd {
34 	struct list_head queue;
35 
36 	u8 type;
37 	u8 pending;
38 
39 	u16 timeout;
40 	struct sk_buff *req;
41 	struct sk_buff *resp;
42 	struct digital_tg_mdaa_params *mdaa_params;
43 
44 	nfc_digital_cmd_complete_t cmd_cb;
45 	void *cb_context;
46 };
47 
48 struct sk_buff *digital_skb_alloc(struct nfc_digital_dev *ddev,
49 				  unsigned int len)
50 {
51 	struct sk_buff *skb;
52 
53 	skb = alloc_skb(len + ddev->tx_headroom + ddev->tx_tailroom,
54 			GFP_KERNEL);
55 	if (skb)
56 		skb_reserve(skb, ddev->tx_headroom);
57 
58 	return skb;
59 }
60 
61 void digital_skb_add_crc(struct sk_buff *skb, crc_func_t crc_func, u16 init,
62 			 u8 bitwise_inv, u8 msb_first)
63 {
64 	u16 crc;
65 
66 	crc = crc_func(init, skb->data, skb->len);
67 
68 	if (bitwise_inv)
69 		crc = ~crc;
70 
71 	if (msb_first)
72 		crc = __fswab16(crc);
73 
74 	*skb_put(skb, 1) = crc & 0xFF;
75 	*skb_put(skb, 1) = (crc >> 8) & 0xFF;
76 }
77 
78 int digital_skb_check_crc(struct sk_buff *skb, crc_func_t crc_func,
79 			  u16 crc_init, u8 bitwise_inv, u8 msb_first)
80 {
81 	int rc;
82 	u16 crc;
83 
84 	if (skb->len <= 2)
85 		return -EIO;
86 
87 	crc = crc_func(crc_init, skb->data, skb->len - 2);
88 
89 	if (bitwise_inv)
90 		crc = ~crc;
91 
92 	if (msb_first)
93 		crc = __swab16(crc);
94 
95 	rc = (skb->data[skb->len - 2] - (crc & 0xFF)) +
96 	     (skb->data[skb->len - 1] - ((crc >> 8) & 0xFF));
97 
98 	if (rc)
99 		return -EIO;
100 
101 	skb_trim(skb, skb->len - 2);
102 
103 	return 0;
104 }
105 
106 static inline void digital_switch_rf(struct nfc_digital_dev *ddev, bool on)
107 {
108 	ddev->ops->switch_rf(ddev, on);
109 }
110 
111 static inline void digital_abort_cmd(struct nfc_digital_dev *ddev)
112 {
113 	ddev->ops->abort_cmd(ddev);
114 }
115 
116 static void digital_wq_cmd_complete(struct work_struct *work)
117 {
118 	struct digital_cmd *cmd;
119 	struct nfc_digital_dev *ddev = container_of(work,
120 						    struct nfc_digital_dev,
121 						    cmd_complete_work);
122 
123 	mutex_lock(&ddev->cmd_lock);
124 
125 	cmd = list_first_entry_or_null(&ddev->cmd_queue, struct digital_cmd,
126 				       queue);
127 	if (!cmd) {
128 		mutex_unlock(&ddev->cmd_lock);
129 		return;
130 	}
131 
132 	list_del(&cmd->queue);
133 
134 	mutex_unlock(&ddev->cmd_lock);
135 
136 	if (!IS_ERR(cmd->resp))
137 		print_hex_dump_debug("DIGITAL RX: ", DUMP_PREFIX_NONE, 16, 1,
138 				     cmd->resp->data, cmd->resp->len, false);
139 
140 	cmd->cmd_cb(ddev, cmd->cb_context, cmd->resp);
141 
142 	kfree(cmd->mdaa_params);
143 	kfree(cmd);
144 
145 	schedule_work(&ddev->cmd_work);
146 }
147 
148 static void digital_send_cmd_complete(struct nfc_digital_dev *ddev,
149 				      void *arg, struct sk_buff *resp)
150 {
151 	struct digital_cmd *cmd = arg;
152 
153 	cmd->resp = resp;
154 
155 	schedule_work(&ddev->cmd_complete_work);
156 }
157 
158 static void digital_wq_cmd(struct work_struct *work)
159 {
160 	int rc;
161 	struct digital_cmd *cmd;
162 	struct digital_tg_mdaa_params *params;
163 	struct nfc_digital_dev *ddev = container_of(work,
164 						    struct nfc_digital_dev,
165 						    cmd_work);
166 
167 	mutex_lock(&ddev->cmd_lock);
168 
169 	cmd = list_first_entry_or_null(&ddev->cmd_queue, struct digital_cmd,
170 				       queue);
171 	if (!cmd || cmd->pending) {
172 		mutex_unlock(&ddev->cmd_lock);
173 		return;
174 	}
175 
176 	mutex_unlock(&ddev->cmd_lock);
177 
178 	if (cmd->req)
179 		print_hex_dump_debug("DIGITAL TX: ", DUMP_PREFIX_NONE, 16, 1,
180 				     cmd->req->data, cmd->req->len, false);
181 
182 	switch (cmd->type) {
183 	case DIGITAL_CMD_IN_SEND:
184 		rc = ddev->ops->in_send_cmd(ddev, cmd->req, cmd->timeout,
185 					    digital_send_cmd_complete, cmd);
186 		break;
187 
188 	case DIGITAL_CMD_TG_SEND:
189 		rc = ddev->ops->tg_send_cmd(ddev, cmd->req, cmd->timeout,
190 					    digital_send_cmd_complete, cmd);
191 		break;
192 
193 	case DIGITAL_CMD_TG_LISTEN:
194 		rc = ddev->ops->tg_listen(ddev, cmd->timeout,
195 					  digital_send_cmd_complete, cmd);
196 		break;
197 
198 	case DIGITAL_CMD_TG_LISTEN_MDAA:
199 		params = cmd->mdaa_params;
200 
201 		rc = ddev->ops->tg_listen_mdaa(ddev, params, cmd->timeout,
202 					       digital_send_cmd_complete, cmd);
203 		break;
204 
205 	case DIGITAL_CMD_TG_LISTEN_MD:
206 		rc = ddev->ops->tg_listen_md(ddev, cmd->timeout,
207 					       digital_send_cmd_complete, cmd);
208 		break;
209 
210 	default:
211 		pr_err("Unknown cmd type %d\n", cmd->type);
212 		return;
213 	}
214 
215 	if (!rc)
216 		return;
217 
218 	pr_err("in_send_command returned err %d\n", rc);
219 
220 	mutex_lock(&ddev->cmd_lock);
221 	list_del(&cmd->queue);
222 	mutex_unlock(&ddev->cmd_lock);
223 
224 	kfree_skb(cmd->req);
225 	kfree(cmd->mdaa_params);
226 	kfree(cmd);
227 
228 	schedule_work(&ddev->cmd_work);
229 }
230 
231 int digital_send_cmd(struct nfc_digital_dev *ddev, u8 cmd_type,
232 		     struct sk_buff *skb, struct digital_tg_mdaa_params *params,
233 		     u16 timeout, nfc_digital_cmd_complete_t cmd_cb,
234 		     void *cb_context)
235 {
236 	struct digital_cmd *cmd;
237 
238 	cmd = kzalloc(sizeof(struct digital_cmd), GFP_KERNEL);
239 	if (!cmd)
240 		return -ENOMEM;
241 
242 	cmd->type = cmd_type;
243 	cmd->timeout = timeout;
244 	cmd->req = skb;
245 	cmd->mdaa_params = params;
246 	cmd->cmd_cb = cmd_cb;
247 	cmd->cb_context = cb_context;
248 	INIT_LIST_HEAD(&cmd->queue);
249 
250 	mutex_lock(&ddev->cmd_lock);
251 	list_add_tail(&cmd->queue, &ddev->cmd_queue);
252 	mutex_unlock(&ddev->cmd_lock);
253 
254 	schedule_work(&ddev->cmd_work);
255 
256 	return 0;
257 }
258 
259 int digital_in_configure_hw(struct nfc_digital_dev *ddev, int type, int param)
260 {
261 	int rc;
262 
263 	rc = ddev->ops->in_configure_hw(ddev, type, param);
264 	if (rc)
265 		pr_err("in_configure_hw failed: %d\n", rc);
266 
267 	return rc;
268 }
269 
270 int digital_tg_configure_hw(struct nfc_digital_dev *ddev, int type, int param)
271 {
272 	int rc;
273 
274 	rc = ddev->ops->tg_configure_hw(ddev, type, param);
275 	if (rc)
276 		pr_err("tg_configure_hw failed: %d\n", rc);
277 
278 	return rc;
279 }
280 
281 static int digital_tg_listen_mdaa(struct nfc_digital_dev *ddev, u8 rf_tech)
282 {
283 	struct digital_tg_mdaa_params *params;
284 
285 	params = kzalloc(sizeof(struct digital_tg_mdaa_params), GFP_KERNEL);
286 	if (!params)
287 		return -ENOMEM;
288 
289 	params->sens_res = DIGITAL_SENS_RES_NFC_DEP;
290 	get_random_bytes(params->nfcid1, sizeof(params->nfcid1));
291 	params->sel_res = DIGITAL_SEL_RES_NFC_DEP;
292 
293 	params->nfcid2[0] = DIGITAL_SENSF_NFCID2_NFC_DEP_B1;
294 	params->nfcid2[1] = DIGITAL_SENSF_NFCID2_NFC_DEP_B2;
295 	get_random_bytes(params->nfcid2 + 2, NFC_NFCID2_MAXSIZE - 2);
296 	params->sc = DIGITAL_SENSF_FELICA_SC;
297 
298 	return digital_send_cmd(ddev, DIGITAL_CMD_TG_LISTEN_MDAA, NULL, params,
299 				500, digital_tg_recv_atr_req, NULL);
300 }
301 
302 static int digital_tg_listen_md(struct nfc_digital_dev *ddev, u8 rf_tech)
303 {
304 	return digital_send_cmd(ddev, DIGITAL_CMD_TG_LISTEN_MD, NULL, NULL, 500,
305 				digital_tg_recv_md_req, NULL);
306 }
307 
308 int digital_target_found(struct nfc_digital_dev *ddev,
309 			 struct nfc_target *target, u8 protocol)
310 {
311 	int rc;
312 	u8 framing;
313 	u8 rf_tech;
314 	u8 poll_tech_count;
315 	int (*check_crc)(struct sk_buff *skb);
316 	void (*add_crc)(struct sk_buff *skb);
317 
318 	rf_tech = ddev->poll_techs[ddev->poll_tech_index].rf_tech;
319 
320 	switch (protocol) {
321 	case NFC_PROTO_JEWEL:
322 		framing = NFC_DIGITAL_FRAMING_NFCA_T1T;
323 		check_crc = digital_skb_check_crc_b;
324 		add_crc = digital_skb_add_crc_b;
325 		break;
326 
327 	case NFC_PROTO_MIFARE:
328 		framing = NFC_DIGITAL_FRAMING_NFCA_T2T;
329 		check_crc = digital_skb_check_crc_a;
330 		add_crc = digital_skb_add_crc_a;
331 		break;
332 
333 	case NFC_PROTO_FELICA:
334 		framing = NFC_DIGITAL_FRAMING_NFCF_T3T;
335 		check_crc = digital_skb_check_crc_f;
336 		add_crc = digital_skb_add_crc_f;
337 		break;
338 
339 	case NFC_PROTO_NFC_DEP:
340 		if (rf_tech == NFC_DIGITAL_RF_TECH_106A) {
341 			framing = NFC_DIGITAL_FRAMING_NFCA_NFC_DEP;
342 			check_crc = digital_skb_check_crc_a;
343 			add_crc = digital_skb_add_crc_a;
344 		} else {
345 			framing = NFC_DIGITAL_FRAMING_NFCF_NFC_DEP;
346 			check_crc = digital_skb_check_crc_f;
347 			add_crc = digital_skb_add_crc_f;
348 		}
349 		break;
350 
351 	case NFC_PROTO_ISO15693:
352 		framing = NFC_DIGITAL_FRAMING_ISO15693_T5T;
353 		check_crc = digital_skb_check_crc_b;
354 		add_crc = digital_skb_add_crc_b;
355 		break;
356 
357 	case NFC_PROTO_ISO14443:
358 		framing = NFC_DIGITAL_FRAMING_NFCA_T4T;
359 		check_crc = digital_skb_check_crc_a;
360 		add_crc = digital_skb_add_crc_a;
361 		break;
362 
363 	case NFC_PROTO_ISO14443_B:
364 		framing = NFC_DIGITAL_FRAMING_NFCB_T4T;
365 		check_crc = digital_skb_check_crc_b;
366 		add_crc = digital_skb_add_crc_b;
367 		break;
368 
369 	default:
370 		pr_err("Invalid protocol %d\n", protocol);
371 		return -EINVAL;
372 	}
373 
374 	pr_debug("rf_tech=%d, protocol=%d\n", rf_tech, protocol);
375 
376 	ddev->curr_rf_tech = rf_tech;
377 
378 	if (DIGITAL_DRV_CAPS_IN_CRC(ddev)) {
379 		ddev->skb_add_crc = digital_skb_add_crc_none;
380 		ddev->skb_check_crc = digital_skb_check_crc_none;
381 	} else {
382 		ddev->skb_add_crc = add_crc;
383 		ddev->skb_check_crc = check_crc;
384 	}
385 
386 	rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING, framing);
387 	if (rc)
388 		return rc;
389 
390 	target->supported_protocols = (1 << protocol);
391 
392 	poll_tech_count = ddev->poll_tech_count;
393 	ddev->poll_tech_count = 0;
394 
395 	rc = nfc_targets_found(ddev->nfc_dev, target, 1);
396 	if (rc) {
397 		ddev->poll_tech_count = poll_tech_count;
398 		return rc;
399 	}
400 
401 	return 0;
402 }
403 
404 void digital_poll_next_tech(struct nfc_digital_dev *ddev)
405 {
406 	u8 rand_mod;
407 
408 	digital_switch_rf(ddev, 0);
409 
410 	mutex_lock(&ddev->poll_lock);
411 
412 	if (!ddev->poll_tech_count) {
413 		mutex_unlock(&ddev->poll_lock);
414 		return;
415 	}
416 
417 	get_random_bytes(&rand_mod, sizeof(rand_mod));
418 	ddev->poll_tech_index = rand_mod % ddev->poll_tech_count;
419 
420 	mutex_unlock(&ddev->poll_lock);
421 
422 	schedule_work(&ddev->poll_work);
423 }
424 
425 static void digital_wq_poll(struct work_struct *work)
426 {
427 	int rc;
428 	struct digital_poll_tech *poll_tech;
429 	struct nfc_digital_dev *ddev = container_of(work,
430 						    struct nfc_digital_dev,
431 						    poll_work);
432 	mutex_lock(&ddev->poll_lock);
433 
434 	if (!ddev->poll_tech_count) {
435 		mutex_unlock(&ddev->poll_lock);
436 		return;
437 	}
438 
439 	poll_tech = &ddev->poll_techs[ddev->poll_tech_index];
440 
441 	mutex_unlock(&ddev->poll_lock);
442 
443 	rc = poll_tech->poll_func(ddev, poll_tech->rf_tech);
444 	if (rc)
445 		digital_poll_next_tech(ddev);
446 }
447 
448 static void digital_add_poll_tech(struct nfc_digital_dev *ddev, u8 rf_tech,
449 				  digital_poll_t poll_func)
450 {
451 	struct digital_poll_tech *poll_tech;
452 
453 	if (ddev->poll_tech_count >= NFC_DIGITAL_POLL_MODE_COUNT_MAX)
454 		return;
455 
456 	poll_tech = &ddev->poll_techs[ddev->poll_tech_count++];
457 
458 	poll_tech->rf_tech = rf_tech;
459 	poll_tech->poll_func = poll_func;
460 }
461 
462 /**
463  * start_poll operation
464  *
465  * For every supported protocol, the corresponding polling function is added
466  * to the table of polling technologies (ddev->poll_techs[]) using
467  * digital_add_poll_tech().
468  * When a polling function fails (by timeout or protocol error) the next one is
469  * schedule by digital_poll_next_tech() on the poll workqueue (ddev->poll_work).
470  */
471 static int digital_start_poll(struct nfc_dev *nfc_dev, __u32 im_protocols,
472 			      __u32 tm_protocols)
473 {
474 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
475 	u32 matching_im_protocols, matching_tm_protocols;
476 
477 	pr_debug("protocols: im 0x%x, tm 0x%x, supported 0x%x\n", im_protocols,
478 		 tm_protocols, ddev->protocols);
479 
480 	matching_im_protocols = ddev->protocols & im_protocols;
481 	matching_tm_protocols = ddev->protocols & tm_protocols;
482 
483 	if (!matching_im_protocols && !matching_tm_protocols) {
484 		pr_err("Unknown protocol\n");
485 		return -EINVAL;
486 	}
487 
488 	if (ddev->poll_tech_count) {
489 		pr_err("Already polling\n");
490 		return -EBUSY;
491 	}
492 
493 	if (ddev->curr_protocol) {
494 		pr_err("A target is already active\n");
495 		return -EBUSY;
496 	}
497 
498 	ddev->poll_tech_count = 0;
499 	ddev->poll_tech_index = 0;
500 
501 	if (matching_im_protocols & DIGITAL_PROTO_NFCA_RF_TECH)
502 		digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_106A,
503 				      digital_in_send_sens_req);
504 
505 	if (matching_im_protocols & DIGITAL_PROTO_NFCB_RF_TECH)
506 		digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_106B,
507 				      digital_in_send_sensb_req);
508 
509 	if (matching_im_protocols & DIGITAL_PROTO_NFCF_RF_TECH) {
510 		digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_212F,
511 				      digital_in_send_sensf_req);
512 
513 		digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_424F,
514 				      digital_in_send_sensf_req);
515 	}
516 
517 	if (matching_im_protocols & DIGITAL_PROTO_ISO15693_RF_TECH)
518 		digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_ISO15693,
519 				      digital_in_send_iso15693_inv_req);
520 
521 	if (matching_tm_protocols & NFC_PROTO_NFC_DEP_MASK) {
522 		if (ddev->ops->tg_listen_mdaa) {
523 			digital_add_poll_tech(ddev, 0,
524 					      digital_tg_listen_mdaa);
525 		} else if (ddev->ops->tg_listen_md) {
526 			digital_add_poll_tech(ddev, 0,
527 					      digital_tg_listen_md);
528 		} else {
529 			digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_106A,
530 					      digital_tg_listen_nfca);
531 
532 			digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_212F,
533 					      digital_tg_listen_nfcf);
534 
535 			digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_424F,
536 					      digital_tg_listen_nfcf);
537 		}
538 	}
539 
540 	if (!ddev->poll_tech_count) {
541 		pr_err("Unsupported protocols: im=0x%x, tm=0x%x\n",
542 		       matching_im_protocols, matching_tm_protocols);
543 		return -EINVAL;
544 	}
545 
546 	schedule_work(&ddev->poll_work);
547 
548 	return 0;
549 }
550 
551 static void digital_stop_poll(struct nfc_dev *nfc_dev)
552 {
553 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
554 
555 	mutex_lock(&ddev->poll_lock);
556 
557 	if (!ddev->poll_tech_count) {
558 		pr_err("Polling operation was not running\n");
559 		mutex_unlock(&ddev->poll_lock);
560 		return;
561 	}
562 
563 	ddev->poll_tech_count = 0;
564 
565 	mutex_unlock(&ddev->poll_lock);
566 
567 	cancel_work_sync(&ddev->poll_work);
568 
569 	digital_abort_cmd(ddev);
570 }
571 
572 static int digital_dev_up(struct nfc_dev *nfc_dev)
573 {
574 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
575 
576 	digital_switch_rf(ddev, 1);
577 
578 	return 0;
579 }
580 
581 static int digital_dev_down(struct nfc_dev *nfc_dev)
582 {
583 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
584 
585 	digital_switch_rf(ddev, 0);
586 
587 	return 0;
588 }
589 
590 static int digital_dep_link_up(struct nfc_dev *nfc_dev,
591 			       struct nfc_target *target,
592 			       __u8 comm_mode, __u8 *gb, size_t gb_len)
593 {
594 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
595 	int rc;
596 
597 	rc = digital_in_send_atr_req(ddev, target, comm_mode, gb, gb_len);
598 
599 	if (!rc)
600 		ddev->curr_protocol = NFC_PROTO_NFC_DEP;
601 
602 	return rc;
603 }
604 
605 static int digital_dep_link_down(struct nfc_dev *nfc_dev)
606 {
607 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
608 
609 	ddev->curr_protocol = 0;
610 
611 	return 0;
612 }
613 
614 static int digital_activate_target(struct nfc_dev *nfc_dev,
615 				   struct nfc_target *target, __u32 protocol)
616 {
617 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
618 
619 	if (ddev->poll_tech_count) {
620 		pr_err("Can't activate a target while polling\n");
621 		return -EBUSY;
622 	}
623 
624 	if (ddev->curr_protocol) {
625 		pr_err("A target is already active\n");
626 		return -EBUSY;
627 	}
628 
629 	ddev->curr_protocol = protocol;
630 
631 	return 0;
632 }
633 
634 static void digital_deactivate_target(struct nfc_dev *nfc_dev,
635 				      struct nfc_target *target,
636 				      u8 mode)
637 {
638 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
639 
640 	if (!ddev->curr_protocol) {
641 		pr_err("No active target\n");
642 		return;
643 	}
644 
645 	ddev->curr_protocol = 0;
646 }
647 
648 static int digital_tg_send(struct nfc_dev *dev, struct sk_buff *skb)
649 {
650 	struct nfc_digital_dev *ddev = nfc_get_drvdata(dev);
651 
652 	return digital_tg_send_dep_res(ddev, skb);
653 }
654 
655 static void digital_in_send_complete(struct nfc_digital_dev *ddev, void *arg,
656 				     struct sk_buff *resp)
657 {
658 	struct digital_data_exch *data_exch = arg;
659 	int rc;
660 
661 	if (IS_ERR(resp)) {
662 		rc = PTR_ERR(resp);
663 		resp = NULL;
664 		goto done;
665 	}
666 
667 	if (ddev->curr_protocol == NFC_PROTO_MIFARE) {
668 		rc = digital_in_recv_mifare_res(resp);
669 		/* crc check is done in digital_in_recv_mifare_res() */
670 		goto done;
671 	}
672 
673 	if ((ddev->curr_protocol == NFC_PROTO_ISO14443) ||
674 	    (ddev->curr_protocol == NFC_PROTO_ISO14443_B)) {
675 		rc = digital_in_iso_dep_pull_sod(ddev, resp);
676 		if (rc)
677 			goto done;
678 	}
679 
680 	rc = ddev->skb_check_crc(resp);
681 
682 done:
683 	if (rc) {
684 		kfree_skb(resp);
685 		resp = NULL;
686 	}
687 
688 	data_exch->cb(data_exch->cb_context, resp, rc);
689 
690 	kfree(data_exch);
691 }
692 
693 static int digital_in_send(struct nfc_dev *nfc_dev, struct nfc_target *target,
694 			   struct sk_buff *skb, data_exchange_cb_t cb,
695 			   void *cb_context)
696 {
697 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
698 	struct digital_data_exch *data_exch;
699 	int rc;
700 
701 	data_exch = kzalloc(sizeof(struct digital_data_exch), GFP_KERNEL);
702 	if (!data_exch) {
703 		pr_err("Failed to allocate data_exch struct\n");
704 		return -ENOMEM;
705 	}
706 
707 	data_exch->cb = cb;
708 	data_exch->cb_context = cb_context;
709 
710 	if (ddev->curr_protocol == NFC_PROTO_NFC_DEP) {
711 		rc = digital_in_send_dep_req(ddev, target, skb, data_exch);
712 		goto exit;
713 	}
714 
715 	if ((ddev->curr_protocol == NFC_PROTO_ISO14443) ||
716 	    (ddev->curr_protocol == NFC_PROTO_ISO14443_B)) {
717 		rc = digital_in_iso_dep_push_sod(ddev, skb);
718 		if (rc)
719 			goto exit;
720 	}
721 
722 	ddev->skb_add_crc(skb);
723 
724 	rc = digital_in_send_cmd(ddev, skb, 500, digital_in_send_complete,
725 				 data_exch);
726 
727 exit:
728 	if (rc)
729 		kfree(data_exch);
730 
731 	return rc;
732 }
733 
734 static struct nfc_ops digital_nfc_ops = {
735 	.dev_up = digital_dev_up,
736 	.dev_down = digital_dev_down,
737 	.start_poll = digital_start_poll,
738 	.stop_poll = digital_stop_poll,
739 	.dep_link_up = digital_dep_link_up,
740 	.dep_link_down = digital_dep_link_down,
741 	.activate_target = digital_activate_target,
742 	.deactivate_target = digital_deactivate_target,
743 	.tm_send = digital_tg_send,
744 	.im_transceive = digital_in_send,
745 };
746 
747 struct nfc_digital_dev *nfc_digital_allocate_device(struct nfc_digital_ops *ops,
748 					    __u32 supported_protocols,
749 					    __u32 driver_capabilities,
750 					    int tx_headroom, int tx_tailroom)
751 {
752 	struct nfc_digital_dev *ddev;
753 
754 	if (!ops->in_configure_hw || !ops->in_send_cmd || !ops->tg_listen ||
755 	    !ops->tg_configure_hw || !ops->tg_send_cmd || !ops->abort_cmd ||
756 	    !ops->switch_rf || (ops->tg_listen_md && !ops->tg_get_rf_tech))
757 		return NULL;
758 
759 	ddev = kzalloc(sizeof(struct nfc_digital_dev), GFP_KERNEL);
760 	if (!ddev)
761 		return NULL;
762 
763 	ddev->driver_capabilities = driver_capabilities;
764 	ddev->ops = ops;
765 
766 	mutex_init(&ddev->cmd_lock);
767 	INIT_LIST_HEAD(&ddev->cmd_queue);
768 
769 	INIT_WORK(&ddev->cmd_work, digital_wq_cmd);
770 	INIT_WORK(&ddev->cmd_complete_work, digital_wq_cmd_complete);
771 
772 	mutex_init(&ddev->poll_lock);
773 	INIT_WORK(&ddev->poll_work, digital_wq_poll);
774 
775 	if (supported_protocols & NFC_PROTO_JEWEL_MASK)
776 		ddev->protocols |= NFC_PROTO_JEWEL_MASK;
777 	if (supported_protocols & NFC_PROTO_MIFARE_MASK)
778 		ddev->protocols |= NFC_PROTO_MIFARE_MASK;
779 	if (supported_protocols & NFC_PROTO_FELICA_MASK)
780 		ddev->protocols |= NFC_PROTO_FELICA_MASK;
781 	if (supported_protocols & NFC_PROTO_NFC_DEP_MASK)
782 		ddev->protocols |= NFC_PROTO_NFC_DEP_MASK;
783 	if (supported_protocols & NFC_PROTO_ISO15693_MASK)
784 		ddev->protocols |= NFC_PROTO_ISO15693_MASK;
785 	if (supported_protocols & NFC_PROTO_ISO14443_MASK)
786 		ddev->protocols |= NFC_PROTO_ISO14443_MASK;
787 	if (supported_protocols & NFC_PROTO_ISO14443_B_MASK)
788 		ddev->protocols |= NFC_PROTO_ISO14443_B_MASK;
789 
790 	ddev->tx_headroom = tx_headroom + DIGITAL_MAX_HEADER_LEN;
791 	ddev->tx_tailroom = tx_tailroom + DIGITAL_CRC_LEN;
792 
793 	ddev->nfc_dev = nfc_allocate_device(&digital_nfc_ops, ddev->protocols,
794 					    ddev->tx_headroom,
795 					    ddev->tx_tailroom);
796 	if (!ddev->nfc_dev) {
797 		pr_err("nfc_allocate_device failed\n");
798 		goto free_dev;
799 	}
800 
801 	nfc_set_drvdata(ddev->nfc_dev, ddev);
802 
803 	return ddev;
804 
805 free_dev:
806 	kfree(ddev);
807 
808 	return NULL;
809 }
810 EXPORT_SYMBOL(nfc_digital_allocate_device);
811 
812 void nfc_digital_free_device(struct nfc_digital_dev *ddev)
813 {
814 	nfc_free_device(ddev->nfc_dev);
815 	kfree(ddev);
816 }
817 EXPORT_SYMBOL(nfc_digital_free_device);
818 
819 int nfc_digital_register_device(struct nfc_digital_dev *ddev)
820 {
821 	return nfc_register_device(ddev->nfc_dev);
822 }
823 EXPORT_SYMBOL(nfc_digital_register_device);
824 
825 void nfc_digital_unregister_device(struct nfc_digital_dev *ddev)
826 {
827 	struct digital_cmd *cmd, *n;
828 
829 	nfc_unregister_device(ddev->nfc_dev);
830 
831 	mutex_lock(&ddev->poll_lock);
832 	ddev->poll_tech_count = 0;
833 	mutex_unlock(&ddev->poll_lock);
834 
835 	cancel_work_sync(&ddev->poll_work);
836 	cancel_work_sync(&ddev->cmd_work);
837 	cancel_work_sync(&ddev->cmd_complete_work);
838 
839 	list_for_each_entry_safe(cmd, n, &ddev->cmd_queue, queue) {
840 		list_del(&cmd->queue);
841 		kfree(cmd->mdaa_params);
842 		kfree(cmd);
843 	}
844 }
845 EXPORT_SYMBOL(nfc_digital_unregister_device);
846 
847 MODULE_LICENSE("GPL");
848