xref: /openbmc/linux/net/nfc/digital_core.c (revision 81de3bf3)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * NFC Digital Protocol stack
4  * Copyright (c) 2013, Intel Corporation.
5  */
6 
7 #define pr_fmt(fmt) "digital: %s: " fmt, __func__
8 
9 #include <linux/module.h>
10 
11 #include "digital.h"
12 
13 #define DIGITAL_PROTO_NFCA_RF_TECH \
14 	(NFC_PROTO_JEWEL_MASK | NFC_PROTO_MIFARE_MASK | \
15 	NFC_PROTO_NFC_DEP_MASK | NFC_PROTO_ISO14443_MASK)
16 
17 #define DIGITAL_PROTO_NFCB_RF_TECH	NFC_PROTO_ISO14443_B_MASK
18 
19 #define DIGITAL_PROTO_NFCF_RF_TECH \
20 	(NFC_PROTO_FELICA_MASK | NFC_PROTO_NFC_DEP_MASK)
21 
22 #define DIGITAL_PROTO_ISO15693_RF_TECH	NFC_PROTO_ISO15693_MASK
23 
24 /* Delay between each poll frame (ms) */
25 #define DIGITAL_POLL_INTERVAL 10
26 
27 struct digital_cmd {
28 	struct list_head queue;
29 
30 	u8 type;
31 	u8 pending;
32 
33 	u16 timeout;
34 	struct sk_buff *req;
35 	struct sk_buff *resp;
36 	struct digital_tg_mdaa_params *mdaa_params;
37 
38 	nfc_digital_cmd_complete_t cmd_cb;
39 	void *cb_context;
40 };
41 
42 struct sk_buff *digital_skb_alloc(struct nfc_digital_dev *ddev,
43 				  unsigned int len)
44 {
45 	struct sk_buff *skb;
46 
47 	skb = alloc_skb(len + ddev->tx_headroom + ddev->tx_tailroom,
48 			GFP_KERNEL);
49 	if (skb)
50 		skb_reserve(skb, ddev->tx_headroom);
51 
52 	return skb;
53 }
54 
55 void digital_skb_add_crc(struct sk_buff *skb, crc_func_t crc_func, u16 init,
56 			 u8 bitwise_inv, u8 msb_first)
57 {
58 	u16 crc;
59 
60 	crc = crc_func(init, skb->data, skb->len);
61 
62 	if (bitwise_inv)
63 		crc = ~crc;
64 
65 	if (msb_first)
66 		crc = __fswab16(crc);
67 
68 	skb_put_u8(skb, crc & 0xFF);
69 	skb_put_u8(skb, (crc >> 8) & 0xFF);
70 }
71 
72 int digital_skb_check_crc(struct sk_buff *skb, crc_func_t crc_func,
73 			  u16 crc_init, u8 bitwise_inv, u8 msb_first)
74 {
75 	int rc;
76 	u16 crc;
77 
78 	if (skb->len <= 2)
79 		return -EIO;
80 
81 	crc = crc_func(crc_init, skb->data, skb->len - 2);
82 
83 	if (bitwise_inv)
84 		crc = ~crc;
85 
86 	if (msb_first)
87 		crc = __swab16(crc);
88 
89 	rc = (skb->data[skb->len - 2] - (crc & 0xFF)) +
90 	     (skb->data[skb->len - 1] - ((crc >> 8) & 0xFF));
91 
92 	if (rc)
93 		return -EIO;
94 
95 	skb_trim(skb, skb->len - 2);
96 
97 	return 0;
98 }
99 
100 static inline void digital_switch_rf(struct nfc_digital_dev *ddev, bool on)
101 {
102 	ddev->ops->switch_rf(ddev, on);
103 }
104 
105 static inline void digital_abort_cmd(struct nfc_digital_dev *ddev)
106 {
107 	ddev->ops->abort_cmd(ddev);
108 }
109 
110 static void digital_wq_cmd_complete(struct work_struct *work)
111 {
112 	struct digital_cmd *cmd;
113 	struct nfc_digital_dev *ddev = container_of(work,
114 						    struct nfc_digital_dev,
115 						    cmd_complete_work);
116 
117 	mutex_lock(&ddev->cmd_lock);
118 
119 	cmd = list_first_entry_or_null(&ddev->cmd_queue, struct digital_cmd,
120 				       queue);
121 	if (!cmd) {
122 		mutex_unlock(&ddev->cmd_lock);
123 		return;
124 	}
125 
126 	list_del(&cmd->queue);
127 
128 	mutex_unlock(&ddev->cmd_lock);
129 
130 	if (!IS_ERR(cmd->resp))
131 		print_hex_dump_debug("DIGITAL RX: ", DUMP_PREFIX_NONE, 16, 1,
132 				     cmd->resp->data, cmd->resp->len, false);
133 
134 	cmd->cmd_cb(ddev, cmd->cb_context, cmd->resp);
135 
136 	kfree(cmd->mdaa_params);
137 	kfree(cmd);
138 
139 	schedule_work(&ddev->cmd_work);
140 }
141 
142 static void digital_send_cmd_complete(struct nfc_digital_dev *ddev,
143 				      void *arg, struct sk_buff *resp)
144 {
145 	struct digital_cmd *cmd = arg;
146 
147 	cmd->resp = resp;
148 
149 	schedule_work(&ddev->cmd_complete_work);
150 }
151 
152 static void digital_wq_cmd(struct work_struct *work)
153 {
154 	int rc;
155 	struct digital_cmd *cmd;
156 	struct digital_tg_mdaa_params *params;
157 	struct nfc_digital_dev *ddev = container_of(work,
158 						    struct nfc_digital_dev,
159 						    cmd_work);
160 
161 	mutex_lock(&ddev->cmd_lock);
162 
163 	cmd = list_first_entry_or_null(&ddev->cmd_queue, struct digital_cmd,
164 				       queue);
165 	if (!cmd || cmd->pending) {
166 		mutex_unlock(&ddev->cmd_lock);
167 		return;
168 	}
169 
170 	cmd->pending = 1;
171 
172 	mutex_unlock(&ddev->cmd_lock);
173 
174 	if (cmd->req)
175 		print_hex_dump_debug("DIGITAL TX: ", DUMP_PREFIX_NONE, 16, 1,
176 				     cmd->req->data, cmd->req->len, false);
177 
178 	switch (cmd->type) {
179 	case DIGITAL_CMD_IN_SEND:
180 		rc = ddev->ops->in_send_cmd(ddev, cmd->req, cmd->timeout,
181 					    digital_send_cmd_complete, cmd);
182 		break;
183 
184 	case DIGITAL_CMD_TG_SEND:
185 		rc = ddev->ops->tg_send_cmd(ddev, cmd->req, cmd->timeout,
186 					    digital_send_cmd_complete, cmd);
187 		break;
188 
189 	case DIGITAL_CMD_TG_LISTEN:
190 		rc = ddev->ops->tg_listen(ddev, cmd->timeout,
191 					  digital_send_cmd_complete, cmd);
192 		break;
193 
194 	case DIGITAL_CMD_TG_LISTEN_MDAA:
195 		params = cmd->mdaa_params;
196 
197 		rc = ddev->ops->tg_listen_mdaa(ddev, params, cmd->timeout,
198 					       digital_send_cmd_complete, cmd);
199 		break;
200 
201 	case DIGITAL_CMD_TG_LISTEN_MD:
202 		rc = ddev->ops->tg_listen_md(ddev, cmd->timeout,
203 					       digital_send_cmd_complete, cmd);
204 		break;
205 
206 	default:
207 		pr_err("Unknown cmd type %d\n", cmd->type);
208 		return;
209 	}
210 
211 	if (!rc)
212 		return;
213 
214 	pr_err("in_send_command returned err %d\n", rc);
215 
216 	mutex_lock(&ddev->cmd_lock);
217 	list_del(&cmd->queue);
218 	mutex_unlock(&ddev->cmd_lock);
219 
220 	kfree_skb(cmd->req);
221 	kfree(cmd->mdaa_params);
222 	kfree(cmd);
223 
224 	schedule_work(&ddev->cmd_work);
225 }
226 
227 int digital_send_cmd(struct nfc_digital_dev *ddev, u8 cmd_type,
228 		     struct sk_buff *skb, struct digital_tg_mdaa_params *params,
229 		     u16 timeout, nfc_digital_cmd_complete_t cmd_cb,
230 		     void *cb_context)
231 {
232 	struct digital_cmd *cmd;
233 
234 	cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
235 	if (!cmd)
236 		return -ENOMEM;
237 
238 	cmd->type = cmd_type;
239 	cmd->timeout = timeout;
240 	cmd->req = skb;
241 	cmd->mdaa_params = params;
242 	cmd->cmd_cb = cmd_cb;
243 	cmd->cb_context = cb_context;
244 	INIT_LIST_HEAD(&cmd->queue);
245 
246 	mutex_lock(&ddev->cmd_lock);
247 	list_add_tail(&cmd->queue, &ddev->cmd_queue);
248 	mutex_unlock(&ddev->cmd_lock);
249 
250 	schedule_work(&ddev->cmd_work);
251 
252 	return 0;
253 }
254 
255 int digital_in_configure_hw(struct nfc_digital_dev *ddev, int type, int param)
256 {
257 	int rc;
258 
259 	rc = ddev->ops->in_configure_hw(ddev, type, param);
260 	if (rc)
261 		pr_err("in_configure_hw failed: %d\n", rc);
262 
263 	return rc;
264 }
265 
266 int digital_tg_configure_hw(struct nfc_digital_dev *ddev, int type, int param)
267 {
268 	int rc;
269 
270 	rc = ddev->ops->tg_configure_hw(ddev, type, param);
271 	if (rc)
272 		pr_err("tg_configure_hw failed: %d\n", rc);
273 
274 	return rc;
275 }
276 
277 static int digital_tg_listen_mdaa(struct nfc_digital_dev *ddev, u8 rf_tech)
278 {
279 	struct digital_tg_mdaa_params *params;
280 
281 	params = kzalloc(sizeof(*params), GFP_KERNEL);
282 	if (!params)
283 		return -ENOMEM;
284 
285 	params->sens_res = DIGITAL_SENS_RES_NFC_DEP;
286 	get_random_bytes(params->nfcid1, sizeof(params->nfcid1));
287 	params->sel_res = DIGITAL_SEL_RES_NFC_DEP;
288 
289 	params->nfcid2[0] = DIGITAL_SENSF_NFCID2_NFC_DEP_B1;
290 	params->nfcid2[1] = DIGITAL_SENSF_NFCID2_NFC_DEP_B2;
291 	get_random_bytes(params->nfcid2 + 2, NFC_NFCID2_MAXSIZE - 2);
292 	params->sc = DIGITAL_SENSF_FELICA_SC;
293 
294 	return digital_send_cmd(ddev, DIGITAL_CMD_TG_LISTEN_MDAA, NULL, params,
295 				500, digital_tg_recv_atr_req, NULL);
296 }
297 
298 static int digital_tg_listen_md(struct nfc_digital_dev *ddev, u8 rf_tech)
299 {
300 	return digital_send_cmd(ddev, DIGITAL_CMD_TG_LISTEN_MD, NULL, NULL, 500,
301 				digital_tg_recv_md_req, NULL);
302 }
303 
304 int digital_target_found(struct nfc_digital_dev *ddev,
305 			 struct nfc_target *target, u8 protocol)
306 {
307 	int rc;
308 	u8 framing;
309 	u8 rf_tech;
310 	u8 poll_tech_count;
311 	int (*check_crc)(struct sk_buff *skb);
312 	void (*add_crc)(struct sk_buff *skb);
313 
314 	rf_tech = ddev->poll_techs[ddev->poll_tech_index].rf_tech;
315 
316 	switch (protocol) {
317 	case NFC_PROTO_JEWEL:
318 		framing = NFC_DIGITAL_FRAMING_NFCA_T1T;
319 		check_crc = digital_skb_check_crc_b;
320 		add_crc = digital_skb_add_crc_b;
321 		break;
322 
323 	case NFC_PROTO_MIFARE:
324 		framing = NFC_DIGITAL_FRAMING_NFCA_T2T;
325 		check_crc = digital_skb_check_crc_a;
326 		add_crc = digital_skb_add_crc_a;
327 		break;
328 
329 	case NFC_PROTO_FELICA:
330 		framing = NFC_DIGITAL_FRAMING_NFCF_T3T;
331 		check_crc = digital_skb_check_crc_f;
332 		add_crc = digital_skb_add_crc_f;
333 		break;
334 
335 	case NFC_PROTO_NFC_DEP:
336 		if (rf_tech == NFC_DIGITAL_RF_TECH_106A) {
337 			framing = NFC_DIGITAL_FRAMING_NFCA_NFC_DEP;
338 			check_crc = digital_skb_check_crc_a;
339 			add_crc = digital_skb_add_crc_a;
340 		} else {
341 			framing = NFC_DIGITAL_FRAMING_NFCF_NFC_DEP;
342 			check_crc = digital_skb_check_crc_f;
343 			add_crc = digital_skb_add_crc_f;
344 		}
345 		break;
346 
347 	case NFC_PROTO_ISO15693:
348 		framing = NFC_DIGITAL_FRAMING_ISO15693_T5T;
349 		check_crc = digital_skb_check_crc_b;
350 		add_crc = digital_skb_add_crc_b;
351 		break;
352 
353 	case NFC_PROTO_ISO14443:
354 		framing = NFC_DIGITAL_FRAMING_NFCA_T4T;
355 		check_crc = digital_skb_check_crc_a;
356 		add_crc = digital_skb_add_crc_a;
357 		break;
358 
359 	case NFC_PROTO_ISO14443_B:
360 		framing = NFC_DIGITAL_FRAMING_NFCB_T4T;
361 		check_crc = digital_skb_check_crc_b;
362 		add_crc = digital_skb_add_crc_b;
363 		break;
364 
365 	default:
366 		pr_err("Invalid protocol %d\n", protocol);
367 		return -EINVAL;
368 	}
369 
370 	pr_debug("rf_tech=%d, protocol=%d\n", rf_tech, protocol);
371 
372 	ddev->curr_rf_tech = rf_tech;
373 
374 	if (DIGITAL_DRV_CAPS_IN_CRC(ddev)) {
375 		ddev->skb_add_crc = digital_skb_add_crc_none;
376 		ddev->skb_check_crc = digital_skb_check_crc_none;
377 	} else {
378 		ddev->skb_add_crc = add_crc;
379 		ddev->skb_check_crc = check_crc;
380 	}
381 
382 	rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING, framing);
383 	if (rc)
384 		return rc;
385 
386 	target->supported_protocols = (1 << protocol);
387 
388 	poll_tech_count = ddev->poll_tech_count;
389 	ddev->poll_tech_count = 0;
390 
391 	rc = nfc_targets_found(ddev->nfc_dev, target, 1);
392 	if (rc) {
393 		ddev->poll_tech_count = poll_tech_count;
394 		return rc;
395 	}
396 
397 	return 0;
398 }
399 
400 void digital_poll_next_tech(struct nfc_digital_dev *ddev)
401 {
402 	u8 rand_mod;
403 
404 	digital_switch_rf(ddev, 0);
405 
406 	mutex_lock(&ddev->poll_lock);
407 
408 	if (!ddev->poll_tech_count) {
409 		mutex_unlock(&ddev->poll_lock);
410 		return;
411 	}
412 
413 	get_random_bytes(&rand_mod, sizeof(rand_mod));
414 	ddev->poll_tech_index = rand_mod % ddev->poll_tech_count;
415 
416 	mutex_unlock(&ddev->poll_lock);
417 
418 	schedule_delayed_work(&ddev->poll_work,
419 			      msecs_to_jiffies(DIGITAL_POLL_INTERVAL));
420 }
421 
422 static void digital_wq_poll(struct work_struct *work)
423 {
424 	int rc;
425 	struct digital_poll_tech *poll_tech;
426 	struct nfc_digital_dev *ddev = container_of(work,
427 						    struct nfc_digital_dev,
428 						    poll_work.work);
429 	mutex_lock(&ddev->poll_lock);
430 
431 	if (!ddev->poll_tech_count) {
432 		mutex_unlock(&ddev->poll_lock);
433 		return;
434 	}
435 
436 	poll_tech = &ddev->poll_techs[ddev->poll_tech_index];
437 
438 	mutex_unlock(&ddev->poll_lock);
439 
440 	rc = poll_tech->poll_func(ddev, poll_tech->rf_tech);
441 	if (rc)
442 		digital_poll_next_tech(ddev);
443 }
444 
445 static void digital_add_poll_tech(struct nfc_digital_dev *ddev, u8 rf_tech,
446 				  digital_poll_t poll_func)
447 {
448 	struct digital_poll_tech *poll_tech;
449 
450 	if (ddev->poll_tech_count >= NFC_DIGITAL_POLL_MODE_COUNT_MAX)
451 		return;
452 
453 	poll_tech = &ddev->poll_techs[ddev->poll_tech_count++];
454 
455 	poll_tech->rf_tech = rf_tech;
456 	poll_tech->poll_func = poll_func;
457 }
458 
459 /**
460  * start_poll operation
461  *
462  * For every supported protocol, the corresponding polling function is added
463  * to the table of polling technologies (ddev->poll_techs[]) using
464  * digital_add_poll_tech().
465  * When a polling function fails (by timeout or protocol error) the next one is
466  * schedule by digital_poll_next_tech() on the poll workqueue (ddev->poll_work).
467  */
468 static int digital_start_poll(struct nfc_dev *nfc_dev, __u32 im_protocols,
469 			      __u32 tm_protocols)
470 {
471 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
472 	u32 matching_im_protocols, matching_tm_protocols;
473 
474 	pr_debug("protocols: im 0x%x, tm 0x%x, supported 0x%x\n", im_protocols,
475 		 tm_protocols, ddev->protocols);
476 
477 	matching_im_protocols = ddev->protocols & im_protocols;
478 	matching_tm_protocols = ddev->protocols & tm_protocols;
479 
480 	if (!matching_im_protocols && !matching_tm_protocols) {
481 		pr_err("Unknown protocol\n");
482 		return -EINVAL;
483 	}
484 
485 	if (ddev->poll_tech_count) {
486 		pr_err("Already polling\n");
487 		return -EBUSY;
488 	}
489 
490 	if (ddev->curr_protocol) {
491 		pr_err("A target is already active\n");
492 		return -EBUSY;
493 	}
494 
495 	ddev->poll_tech_count = 0;
496 	ddev->poll_tech_index = 0;
497 
498 	if (matching_im_protocols & DIGITAL_PROTO_NFCA_RF_TECH)
499 		digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_106A,
500 				      digital_in_send_sens_req);
501 
502 	if (matching_im_protocols & DIGITAL_PROTO_NFCB_RF_TECH)
503 		digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_106B,
504 				      digital_in_send_sensb_req);
505 
506 	if (matching_im_protocols & DIGITAL_PROTO_NFCF_RF_TECH) {
507 		digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_212F,
508 				      digital_in_send_sensf_req);
509 
510 		digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_424F,
511 				      digital_in_send_sensf_req);
512 	}
513 
514 	if (matching_im_protocols & DIGITAL_PROTO_ISO15693_RF_TECH)
515 		digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_ISO15693,
516 				      digital_in_send_iso15693_inv_req);
517 
518 	if (matching_tm_protocols & NFC_PROTO_NFC_DEP_MASK) {
519 		if (ddev->ops->tg_listen_mdaa) {
520 			digital_add_poll_tech(ddev, 0,
521 					      digital_tg_listen_mdaa);
522 		} else if (ddev->ops->tg_listen_md) {
523 			digital_add_poll_tech(ddev, 0,
524 					      digital_tg_listen_md);
525 		} else {
526 			digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_106A,
527 					      digital_tg_listen_nfca);
528 
529 			digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_212F,
530 					      digital_tg_listen_nfcf);
531 
532 			digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_424F,
533 					      digital_tg_listen_nfcf);
534 		}
535 	}
536 
537 	if (!ddev->poll_tech_count) {
538 		pr_err("Unsupported protocols: im=0x%x, tm=0x%x\n",
539 		       matching_im_protocols, matching_tm_protocols);
540 		return -EINVAL;
541 	}
542 
543 	schedule_delayed_work(&ddev->poll_work, 0);
544 
545 	return 0;
546 }
547 
548 static void digital_stop_poll(struct nfc_dev *nfc_dev)
549 {
550 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
551 
552 	mutex_lock(&ddev->poll_lock);
553 
554 	if (!ddev->poll_tech_count) {
555 		pr_err("Polling operation was not running\n");
556 		mutex_unlock(&ddev->poll_lock);
557 		return;
558 	}
559 
560 	ddev->poll_tech_count = 0;
561 
562 	mutex_unlock(&ddev->poll_lock);
563 
564 	cancel_delayed_work_sync(&ddev->poll_work);
565 
566 	digital_abort_cmd(ddev);
567 }
568 
569 static int digital_dev_up(struct nfc_dev *nfc_dev)
570 {
571 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
572 
573 	digital_switch_rf(ddev, 1);
574 
575 	return 0;
576 }
577 
578 static int digital_dev_down(struct nfc_dev *nfc_dev)
579 {
580 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
581 
582 	digital_switch_rf(ddev, 0);
583 
584 	return 0;
585 }
586 
587 static int digital_dep_link_up(struct nfc_dev *nfc_dev,
588 			       struct nfc_target *target,
589 			       __u8 comm_mode, __u8 *gb, size_t gb_len)
590 {
591 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
592 	int rc;
593 
594 	rc = digital_in_send_atr_req(ddev, target, comm_mode, gb, gb_len);
595 
596 	if (!rc)
597 		ddev->curr_protocol = NFC_PROTO_NFC_DEP;
598 
599 	return rc;
600 }
601 
602 static int digital_dep_link_down(struct nfc_dev *nfc_dev)
603 {
604 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
605 
606 	digital_abort_cmd(ddev);
607 
608 	ddev->curr_protocol = 0;
609 
610 	return 0;
611 }
612 
613 static int digital_activate_target(struct nfc_dev *nfc_dev,
614 				   struct nfc_target *target, __u32 protocol)
615 {
616 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
617 
618 	if (ddev->poll_tech_count) {
619 		pr_err("Can't activate a target while polling\n");
620 		return -EBUSY;
621 	}
622 
623 	if (ddev->curr_protocol) {
624 		pr_err("A target is already active\n");
625 		return -EBUSY;
626 	}
627 
628 	ddev->curr_protocol = protocol;
629 
630 	return 0;
631 }
632 
633 static void digital_deactivate_target(struct nfc_dev *nfc_dev,
634 				      struct nfc_target *target,
635 				      u8 mode)
636 {
637 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
638 
639 	if (!ddev->curr_protocol) {
640 		pr_err("No active target\n");
641 		return;
642 	}
643 
644 	digital_abort_cmd(ddev);
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(*data_exch), GFP_KERNEL);
702 	if (!data_exch)
703 		return -ENOMEM;
704 
705 	data_exch->cb = cb;
706 	data_exch->cb_context = cb_context;
707 
708 	if (ddev->curr_protocol == NFC_PROTO_NFC_DEP) {
709 		rc = digital_in_send_dep_req(ddev, target, skb, data_exch);
710 		goto exit;
711 	}
712 
713 	if ((ddev->curr_protocol == NFC_PROTO_ISO14443) ||
714 	    (ddev->curr_protocol == NFC_PROTO_ISO14443_B)) {
715 		rc = digital_in_iso_dep_push_sod(ddev, skb);
716 		if (rc)
717 			goto exit;
718 	}
719 
720 	ddev->skb_add_crc(skb);
721 
722 	rc = digital_in_send_cmd(ddev, skb, 500, digital_in_send_complete,
723 				 data_exch);
724 
725 exit:
726 	if (rc)
727 		kfree(data_exch);
728 
729 	return rc;
730 }
731 
732 static struct nfc_ops digital_nfc_ops = {
733 	.dev_up = digital_dev_up,
734 	.dev_down = digital_dev_down,
735 	.start_poll = digital_start_poll,
736 	.stop_poll = digital_stop_poll,
737 	.dep_link_up = digital_dep_link_up,
738 	.dep_link_down = digital_dep_link_down,
739 	.activate_target = digital_activate_target,
740 	.deactivate_target = digital_deactivate_target,
741 	.tm_send = digital_tg_send,
742 	.im_transceive = digital_in_send,
743 };
744 
745 struct nfc_digital_dev *nfc_digital_allocate_device(struct nfc_digital_ops *ops,
746 					    __u32 supported_protocols,
747 					    __u32 driver_capabilities,
748 					    int tx_headroom, int tx_tailroom)
749 {
750 	struct nfc_digital_dev *ddev;
751 
752 	if (!ops->in_configure_hw || !ops->in_send_cmd || !ops->tg_listen ||
753 	    !ops->tg_configure_hw || !ops->tg_send_cmd || !ops->abort_cmd ||
754 	    !ops->switch_rf || (ops->tg_listen_md && !ops->tg_get_rf_tech))
755 		return NULL;
756 
757 	ddev = kzalloc(sizeof(*ddev), GFP_KERNEL);
758 	if (!ddev)
759 		return NULL;
760 
761 	ddev->driver_capabilities = driver_capabilities;
762 	ddev->ops = ops;
763 
764 	mutex_init(&ddev->cmd_lock);
765 	INIT_LIST_HEAD(&ddev->cmd_queue);
766 
767 	INIT_WORK(&ddev->cmd_work, digital_wq_cmd);
768 	INIT_WORK(&ddev->cmd_complete_work, digital_wq_cmd_complete);
769 
770 	mutex_init(&ddev->poll_lock);
771 	INIT_DELAYED_WORK(&ddev->poll_work, digital_wq_poll);
772 
773 	if (supported_protocols & NFC_PROTO_JEWEL_MASK)
774 		ddev->protocols |= NFC_PROTO_JEWEL_MASK;
775 	if (supported_protocols & NFC_PROTO_MIFARE_MASK)
776 		ddev->protocols |= NFC_PROTO_MIFARE_MASK;
777 	if (supported_protocols & NFC_PROTO_FELICA_MASK)
778 		ddev->protocols |= NFC_PROTO_FELICA_MASK;
779 	if (supported_protocols & NFC_PROTO_NFC_DEP_MASK)
780 		ddev->protocols |= NFC_PROTO_NFC_DEP_MASK;
781 	if (supported_protocols & NFC_PROTO_ISO15693_MASK)
782 		ddev->protocols |= NFC_PROTO_ISO15693_MASK;
783 	if (supported_protocols & NFC_PROTO_ISO14443_MASK)
784 		ddev->protocols |= NFC_PROTO_ISO14443_MASK;
785 	if (supported_protocols & NFC_PROTO_ISO14443_B_MASK)
786 		ddev->protocols |= NFC_PROTO_ISO14443_B_MASK;
787 
788 	ddev->tx_headroom = tx_headroom + DIGITAL_MAX_HEADER_LEN;
789 	ddev->tx_tailroom = tx_tailroom + DIGITAL_CRC_LEN;
790 
791 	ddev->nfc_dev = nfc_allocate_device(&digital_nfc_ops, ddev->protocols,
792 					    ddev->tx_headroom,
793 					    ddev->tx_tailroom);
794 	if (!ddev->nfc_dev) {
795 		pr_err("nfc_allocate_device failed\n");
796 		goto free_dev;
797 	}
798 
799 	nfc_set_drvdata(ddev->nfc_dev, ddev);
800 
801 	return ddev;
802 
803 free_dev:
804 	kfree(ddev);
805 
806 	return NULL;
807 }
808 EXPORT_SYMBOL(nfc_digital_allocate_device);
809 
810 void nfc_digital_free_device(struct nfc_digital_dev *ddev)
811 {
812 	nfc_free_device(ddev->nfc_dev);
813 	kfree(ddev);
814 }
815 EXPORT_SYMBOL(nfc_digital_free_device);
816 
817 int nfc_digital_register_device(struct nfc_digital_dev *ddev)
818 {
819 	return nfc_register_device(ddev->nfc_dev);
820 }
821 EXPORT_SYMBOL(nfc_digital_register_device);
822 
823 void nfc_digital_unregister_device(struct nfc_digital_dev *ddev)
824 {
825 	struct digital_cmd *cmd, *n;
826 
827 	nfc_unregister_device(ddev->nfc_dev);
828 
829 	mutex_lock(&ddev->poll_lock);
830 	ddev->poll_tech_count = 0;
831 	mutex_unlock(&ddev->poll_lock);
832 
833 	cancel_delayed_work_sync(&ddev->poll_work);
834 	cancel_work_sync(&ddev->cmd_work);
835 	cancel_work_sync(&ddev->cmd_complete_work);
836 
837 	list_for_each_entry_safe(cmd, n, &ddev->cmd_queue, queue) {
838 		list_del(&cmd->queue);
839 
840 		/* Call the command callback if any and pass it a ENODEV error.
841 		 * This gives a chance to the command issuer to free any
842 		 * allocated buffer.
843 		 */
844 		if (cmd->cmd_cb)
845 			cmd->cmd_cb(ddev, cmd->cb_context, ERR_PTR(-ENODEV));
846 
847 		kfree(cmd->mdaa_params);
848 		kfree(cmd);
849 	}
850 }
851 EXPORT_SYMBOL(nfc_digital_unregister_device);
852 
853 MODULE_LICENSE("GPL");
854