xref: /openbmc/linux/net/nfc/digital_core.c (revision e65e175b)
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 	int rc;
281 
282 	params = kzalloc(sizeof(*params), GFP_KERNEL);
283 	if (!params)
284 		return -ENOMEM;
285 
286 	params->sens_res = DIGITAL_SENS_RES_NFC_DEP;
287 	get_random_bytes(params->nfcid1, sizeof(params->nfcid1));
288 	params->sel_res = DIGITAL_SEL_RES_NFC_DEP;
289 
290 	params->nfcid2[0] = DIGITAL_SENSF_NFCID2_NFC_DEP_B1;
291 	params->nfcid2[1] = DIGITAL_SENSF_NFCID2_NFC_DEP_B2;
292 	get_random_bytes(params->nfcid2 + 2, NFC_NFCID2_MAXSIZE - 2);
293 	params->sc = DIGITAL_SENSF_FELICA_SC;
294 
295 	rc = digital_send_cmd(ddev, DIGITAL_CMD_TG_LISTEN_MDAA, NULL, params,
296 			      500, digital_tg_recv_atr_req, NULL);
297 	if (rc)
298 		kfree(params);
299 
300 	return rc;
301 }
302 
303 static int digital_tg_listen_md(struct nfc_digital_dev *ddev, u8 rf_tech)
304 {
305 	return digital_send_cmd(ddev, DIGITAL_CMD_TG_LISTEN_MD, NULL, NULL, 500,
306 				digital_tg_recv_md_req, NULL);
307 }
308 
309 int digital_target_found(struct nfc_digital_dev *ddev,
310 			 struct nfc_target *target, u8 protocol)
311 {
312 	int rc;
313 	u8 framing;
314 	u8 rf_tech;
315 	u8 poll_tech_count;
316 	int (*check_crc)(struct sk_buff *skb);
317 	void (*add_crc)(struct sk_buff *skb);
318 
319 	rf_tech = ddev->poll_techs[ddev->poll_tech_index].rf_tech;
320 
321 	switch (protocol) {
322 	case NFC_PROTO_JEWEL:
323 		framing = NFC_DIGITAL_FRAMING_NFCA_T1T;
324 		check_crc = digital_skb_check_crc_b;
325 		add_crc = digital_skb_add_crc_b;
326 		break;
327 
328 	case NFC_PROTO_MIFARE:
329 		framing = NFC_DIGITAL_FRAMING_NFCA_T2T;
330 		check_crc = digital_skb_check_crc_a;
331 		add_crc = digital_skb_add_crc_a;
332 		break;
333 
334 	case NFC_PROTO_FELICA:
335 		framing = NFC_DIGITAL_FRAMING_NFCF_T3T;
336 		check_crc = digital_skb_check_crc_f;
337 		add_crc = digital_skb_add_crc_f;
338 		break;
339 
340 	case NFC_PROTO_NFC_DEP:
341 		if (rf_tech == NFC_DIGITAL_RF_TECH_106A) {
342 			framing = NFC_DIGITAL_FRAMING_NFCA_NFC_DEP;
343 			check_crc = digital_skb_check_crc_a;
344 			add_crc = digital_skb_add_crc_a;
345 		} else {
346 			framing = NFC_DIGITAL_FRAMING_NFCF_NFC_DEP;
347 			check_crc = digital_skb_check_crc_f;
348 			add_crc = digital_skb_add_crc_f;
349 		}
350 		break;
351 
352 	case NFC_PROTO_ISO15693:
353 		framing = NFC_DIGITAL_FRAMING_ISO15693_T5T;
354 		check_crc = digital_skb_check_crc_b;
355 		add_crc = digital_skb_add_crc_b;
356 		break;
357 
358 	case NFC_PROTO_ISO14443:
359 		framing = NFC_DIGITAL_FRAMING_NFCA_T4T;
360 		check_crc = digital_skb_check_crc_a;
361 		add_crc = digital_skb_add_crc_a;
362 		break;
363 
364 	case NFC_PROTO_ISO14443_B:
365 		framing = NFC_DIGITAL_FRAMING_NFCB_T4T;
366 		check_crc = digital_skb_check_crc_b;
367 		add_crc = digital_skb_add_crc_b;
368 		break;
369 
370 	default:
371 		pr_err("Invalid protocol %d\n", protocol);
372 		return -EINVAL;
373 	}
374 
375 	pr_debug("rf_tech=%d, protocol=%d\n", rf_tech, protocol);
376 
377 	ddev->curr_rf_tech = rf_tech;
378 
379 	if (DIGITAL_DRV_CAPS_IN_CRC(ddev)) {
380 		ddev->skb_add_crc = digital_skb_add_crc_none;
381 		ddev->skb_check_crc = digital_skb_check_crc_none;
382 	} else {
383 		ddev->skb_add_crc = add_crc;
384 		ddev->skb_check_crc = check_crc;
385 	}
386 
387 	rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING, framing);
388 	if (rc)
389 		return rc;
390 
391 	target->supported_protocols = (1 << protocol);
392 
393 	poll_tech_count = ddev->poll_tech_count;
394 	ddev->poll_tech_count = 0;
395 
396 	rc = nfc_targets_found(ddev->nfc_dev, target, 1);
397 	if (rc) {
398 		ddev->poll_tech_count = poll_tech_count;
399 		return rc;
400 	}
401 
402 	return 0;
403 }
404 
405 void digital_poll_next_tech(struct nfc_digital_dev *ddev)
406 {
407 	u8 rand_mod;
408 
409 	digital_switch_rf(ddev, 0);
410 
411 	mutex_lock(&ddev->poll_lock);
412 
413 	if (!ddev->poll_tech_count) {
414 		mutex_unlock(&ddev->poll_lock);
415 		return;
416 	}
417 
418 	get_random_bytes(&rand_mod, sizeof(rand_mod));
419 	ddev->poll_tech_index = rand_mod % ddev->poll_tech_count;
420 
421 	mutex_unlock(&ddev->poll_lock);
422 
423 	schedule_delayed_work(&ddev->poll_work,
424 			      msecs_to_jiffies(DIGITAL_POLL_INTERVAL));
425 }
426 
427 static void digital_wq_poll(struct work_struct *work)
428 {
429 	int rc;
430 	struct digital_poll_tech *poll_tech;
431 	struct nfc_digital_dev *ddev = container_of(work,
432 						    struct nfc_digital_dev,
433 						    poll_work.work);
434 	mutex_lock(&ddev->poll_lock);
435 
436 	if (!ddev->poll_tech_count) {
437 		mutex_unlock(&ddev->poll_lock);
438 		return;
439 	}
440 
441 	poll_tech = &ddev->poll_techs[ddev->poll_tech_index];
442 
443 	mutex_unlock(&ddev->poll_lock);
444 
445 	rc = poll_tech->poll_func(ddev, poll_tech->rf_tech);
446 	if (rc)
447 		digital_poll_next_tech(ddev);
448 }
449 
450 static void digital_add_poll_tech(struct nfc_digital_dev *ddev, u8 rf_tech,
451 				  digital_poll_t poll_func)
452 {
453 	struct digital_poll_tech *poll_tech;
454 
455 	if (ddev->poll_tech_count >= NFC_DIGITAL_POLL_MODE_COUNT_MAX)
456 		return;
457 
458 	poll_tech = &ddev->poll_techs[ddev->poll_tech_count++];
459 
460 	poll_tech->rf_tech = rf_tech;
461 	poll_tech->poll_func = poll_func;
462 }
463 
464 /**
465  * digital_start_poll - start_poll operation
466  * @nfc_dev: device to be polled
467  * @im_protocols: bitset of nfc initiator protocols to be used for polling
468  * @tm_protocols: bitset of nfc transport protocols to be used for polling
469  *
470  * For every supported protocol, the corresponding polling function is added
471  * to the table of polling technologies (ddev->poll_techs[]) using
472  * digital_add_poll_tech().
473  * When a polling function fails (by timeout or protocol error) the next one is
474  * schedule by digital_poll_next_tech() on the poll workqueue (ddev->poll_work).
475  */
476 static int digital_start_poll(struct nfc_dev *nfc_dev, __u32 im_protocols,
477 			      __u32 tm_protocols)
478 {
479 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
480 	u32 matching_im_protocols, matching_tm_protocols;
481 
482 	pr_debug("protocols: im 0x%x, tm 0x%x, supported 0x%x\n", im_protocols,
483 		 tm_protocols, ddev->protocols);
484 
485 	matching_im_protocols = ddev->protocols & im_protocols;
486 	matching_tm_protocols = ddev->protocols & tm_protocols;
487 
488 	if (!matching_im_protocols && !matching_tm_protocols) {
489 		pr_err("Unknown protocol\n");
490 		return -EINVAL;
491 	}
492 
493 	if (ddev->poll_tech_count) {
494 		pr_err("Already polling\n");
495 		return -EBUSY;
496 	}
497 
498 	if (ddev->curr_protocol) {
499 		pr_err("A target is already active\n");
500 		return -EBUSY;
501 	}
502 
503 	ddev->poll_tech_count = 0;
504 	ddev->poll_tech_index = 0;
505 
506 	if (matching_im_protocols & DIGITAL_PROTO_NFCA_RF_TECH)
507 		digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_106A,
508 				      digital_in_send_sens_req);
509 
510 	if (matching_im_protocols & DIGITAL_PROTO_NFCB_RF_TECH)
511 		digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_106B,
512 				      digital_in_send_sensb_req);
513 
514 	if (matching_im_protocols & DIGITAL_PROTO_NFCF_RF_TECH) {
515 		digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_212F,
516 				      digital_in_send_sensf_req);
517 
518 		digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_424F,
519 				      digital_in_send_sensf_req);
520 	}
521 
522 	if (matching_im_protocols & DIGITAL_PROTO_ISO15693_RF_TECH)
523 		digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_ISO15693,
524 				      digital_in_send_iso15693_inv_req);
525 
526 	if (matching_tm_protocols & NFC_PROTO_NFC_DEP_MASK) {
527 		if (ddev->ops->tg_listen_mdaa) {
528 			digital_add_poll_tech(ddev, 0,
529 					      digital_tg_listen_mdaa);
530 		} else if (ddev->ops->tg_listen_md) {
531 			digital_add_poll_tech(ddev, 0,
532 					      digital_tg_listen_md);
533 		} else {
534 			digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_106A,
535 					      digital_tg_listen_nfca);
536 
537 			digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_212F,
538 					      digital_tg_listen_nfcf);
539 
540 			digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_424F,
541 					      digital_tg_listen_nfcf);
542 		}
543 	}
544 
545 	if (!ddev->poll_tech_count) {
546 		pr_err("Unsupported protocols: im=0x%x, tm=0x%x\n",
547 		       matching_im_protocols, matching_tm_protocols);
548 		return -EINVAL;
549 	}
550 
551 	schedule_delayed_work(&ddev->poll_work, 0);
552 
553 	return 0;
554 }
555 
556 static void digital_stop_poll(struct nfc_dev *nfc_dev)
557 {
558 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
559 
560 	mutex_lock(&ddev->poll_lock);
561 
562 	if (!ddev->poll_tech_count) {
563 		pr_err("Polling operation was not running\n");
564 		mutex_unlock(&ddev->poll_lock);
565 		return;
566 	}
567 
568 	ddev->poll_tech_count = 0;
569 
570 	mutex_unlock(&ddev->poll_lock);
571 
572 	cancel_delayed_work_sync(&ddev->poll_work);
573 
574 	digital_abort_cmd(ddev);
575 }
576 
577 static int digital_dev_up(struct nfc_dev *nfc_dev)
578 {
579 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
580 
581 	digital_switch_rf(ddev, 1);
582 
583 	return 0;
584 }
585 
586 static int digital_dev_down(struct nfc_dev *nfc_dev)
587 {
588 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
589 
590 	digital_switch_rf(ddev, 0);
591 
592 	return 0;
593 }
594 
595 static int digital_dep_link_up(struct nfc_dev *nfc_dev,
596 			       struct nfc_target *target,
597 			       __u8 comm_mode, __u8 *gb, size_t gb_len)
598 {
599 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
600 	int rc;
601 
602 	rc = digital_in_send_atr_req(ddev, target, comm_mode, gb, gb_len);
603 
604 	if (!rc)
605 		ddev->curr_protocol = NFC_PROTO_NFC_DEP;
606 
607 	return rc;
608 }
609 
610 static int digital_dep_link_down(struct nfc_dev *nfc_dev)
611 {
612 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
613 
614 	digital_abort_cmd(ddev);
615 
616 	ddev->curr_protocol = 0;
617 
618 	return 0;
619 }
620 
621 static int digital_activate_target(struct nfc_dev *nfc_dev,
622 				   struct nfc_target *target, __u32 protocol)
623 {
624 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
625 
626 	if (ddev->poll_tech_count) {
627 		pr_err("Can't activate a target while polling\n");
628 		return -EBUSY;
629 	}
630 
631 	if (ddev->curr_protocol) {
632 		pr_err("A target is already active\n");
633 		return -EBUSY;
634 	}
635 
636 	ddev->curr_protocol = protocol;
637 
638 	return 0;
639 }
640 
641 static void digital_deactivate_target(struct nfc_dev *nfc_dev,
642 				      struct nfc_target *target,
643 				      u8 mode)
644 {
645 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
646 
647 	if (!ddev->curr_protocol) {
648 		pr_err("No active target\n");
649 		return;
650 	}
651 
652 	digital_abort_cmd(ddev);
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(*data_exch), GFP_KERNEL);
710 	if (!data_exch)
711 		return -ENOMEM;
712 
713 	data_exch->cb = cb;
714 	data_exch->cb_context = cb_context;
715 
716 	if (ddev->curr_protocol == NFC_PROTO_NFC_DEP) {
717 		rc = digital_in_send_dep_req(ddev, target, skb, data_exch);
718 		goto exit;
719 	}
720 
721 	if ((ddev->curr_protocol == NFC_PROTO_ISO14443) ||
722 	    (ddev->curr_protocol == NFC_PROTO_ISO14443_B)) {
723 		rc = digital_in_iso_dep_push_sod(ddev, skb);
724 		if (rc)
725 			goto exit;
726 	}
727 
728 	ddev->skb_add_crc(skb);
729 
730 	rc = digital_in_send_cmd(ddev, skb, 500, digital_in_send_complete,
731 				 data_exch);
732 
733 exit:
734 	if (rc)
735 		kfree(data_exch);
736 
737 	return rc;
738 }
739 
740 static const struct nfc_ops digital_nfc_ops = {
741 	.dev_up = digital_dev_up,
742 	.dev_down = digital_dev_down,
743 	.start_poll = digital_start_poll,
744 	.stop_poll = digital_stop_poll,
745 	.dep_link_up = digital_dep_link_up,
746 	.dep_link_down = digital_dep_link_down,
747 	.activate_target = digital_activate_target,
748 	.deactivate_target = digital_deactivate_target,
749 	.tm_send = digital_tg_send,
750 	.im_transceive = digital_in_send,
751 };
752 
753 struct nfc_digital_dev *nfc_digital_allocate_device(const struct nfc_digital_ops *ops,
754 					    __u32 supported_protocols,
755 					    __u32 driver_capabilities,
756 					    int tx_headroom, int tx_tailroom)
757 {
758 	struct nfc_digital_dev *ddev;
759 
760 	if (!ops->in_configure_hw || !ops->in_send_cmd || !ops->tg_listen ||
761 	    !ops->tg_configure_hw || !ops->tg_send_cmd || !ops->abort_cmd ||
762 	    !ops->switch_rf || (ops->tg_listen_md && !ops->tg_get_rf_tech))
763 		return NULL;
764 
765 	ddev = kzalloc(sizeof(*ddev), GFP_KERNEL);
766 	if (!ddev)
767 		return NULL;
768 
769 	ddev->driver_capabilities = driver_capabilities;
770 	ddev->ops = ops;
771 
772 	mutex_init(&ddev->cmd_lock);
773 	INIT_LIST_HEAD(&ddev->cmd_queue);
774 
775 	INIT_WORK(&ddev->cmd_work, digital_wq_cmd);
776 	INIT_WORK(&ddev->cmd_complete_work, digital_wq_cmd_complete);
777 
778 	mutex_init(&ddev->poll_lock);
779 	INIT_DELAYED_WORK(&ddev->poll_work, digital_wq_poll);
780 
781 	if (supported_protocols & NFC_PROTO_JEWEL_MASK)
782 		ddev->protocols |= NFC_PROTO_JEWEL_MASK;
783 	if (supported_protocols & NFC_PROTO_MIFARE_MASK)
784 		ddev->protocols |= NFC_PROTO_MIFARE_MASK;
785 	if (supported_protocols & NFC_PROTO_FELICA_MASK)
786 		ddev->protocols |= NFC_PROTO_FELICA_MASK;
787 	if (supported_protocols & NFC_PROTO_NFC_DEP_MASK)
788 		ddev->protocols |= NFC_PROTO_NFC_DEP_MASK;
789 	if (supported_protocols & NFC_PROTO_ISO15693_MASK)
790 		ddev->protocols |= NFC_PROTO_ISO15693_MASK;
791 	if (supported_protocols & NFC_PROTO_ISO14443_MASK)
792 		ddev->protocols |= NFC_PROTO_ISO14443_MASK;
793 	if (supported_protocols & NFC_PROTO_ISO14443_B_MASK)
794 		ddev->protocols |= NFC_PROTO_ISO14443_B_MASK;
795 
796 	ddev->tx_headroom = tx_headroom + DIGITAL_MAX_HEADER_LEN;
797 	ddev->tx_tailroom = tx_tailroom + DIGITAL_CRC_LEN;
798 
799 	ddev->nfc_dev = nfc_allocate_device(&digital_nfc_ops, ddev->protocols,
800 					    ddev->tx_headroom,
801 					    ddev->tx_tailroom);
802 	if (!ddev->nfc_dev) {
803 		pr_err("nfc_allocate_device failed\n");
804 		goto free_dev;
805 	}
806 
807 	nfc_set_drvdata(ddev->nfc_dev, ddev);
808 
809 	return ddev;
810 
811 free_dev:
812 	kfree(ddev);
813 
814 	return NULL;
815 }
816 EXPORT_SYMBOL(nfc_digital_allocate_device);
817 
818 void nfc_digital_free_device(struct nfc_digital_dev *ddev)
819 {
820 	nfc_free_device(ddev->nfc_dev);
821 	kfree(ddev);
822 }
823 EXPORT_SYMBOL(nfc_digital_free_device);
824 
825 int nfc_digital_register_device(struct nfc_digital_dev *ddev)
826 {
827 	return nfc_register_device(ddev->nfc_dev);
828 }
829 EXPORT_SYMBOL(nfc_digital_register_device);
830 
831 void nfc_digital_unregister_device(struct nfc_digital_dev *ddev)
832 {
833 	struct digital_cmd *cmd, *n;
834 
835 	nfc_unregister_device(ddev->nfc_dev);
836 
837 	mutex_lock(&ddev->poll_lock);
838 	ddev->poll_tech_count = 0;
839 	mutex_unlock(&ddev->poll_lock);
840 
841 	cancel_delayed_work_sync(&ddev->poll_work);
842 	cancel_work_sync(&ddev->cmd_work);
843 	cancel_work_sync(&ddev->cmd_complete_work);
844 
845 	list_for_each_entry_safe(cmd, n, &ddev->cmd_queue, queue) {
846 		list_del(&cmd->queue);
847 
848 		/* Call the command callback if any and pass it a ENODEV error.
849 		 * This gives a chance to the command issuer to free any
850 		 * allocated buffer.
851 		 */
852 		if (cmd->cmd_cb)
853 			cmd->cmd_cb(ddev, cmd->cb_context, ERR_PTR(-ENODEV));
854 
855 		kfree(cmd->mdaa_params);
856 		kfree(cmd);
857 	}
858 }
859 EXPORT_SYMBOL(nfc_digital_unregister_device);
860 
861 MODULE_LICENSE("GPL");
862