xref: /openbmc/linux/net/nfc/hci/core.c (revision ae213c44)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2012  Intel Corporation. All rights reserved.
4  */
5 
6 #define pr_fmt(fmt) "hci: %s: " fmt, __func__
7 
8 #include <linux/init.h>
9 #include <linux/kernel.h>
10 #include <linux/module.h>
11 #include <linux/nfc.h>
12 
13 #include <net/nfc/nfc.h>
14 #include <net/nfc/hci.h>
15 #include <net/nfc/llc.h>
16 
17 #include "hci.h"
18 
19 /* Largest headroom needed for outgoing HCI commands */
20 #define HCI_CMDS_HEADROOM 1
21 
22 int nfc_hci_result_to_errno(u8 result)
23 {
24 	switch (result) {
25 	case NFC_HCI_ANY_OK:
26 		return 0;
27 	case NFC_HCI_ANY_E_REG_PAR_UNKNOWN:
28 		return -EOPNOTSUPP;
29 	case NFC_HCI_ANY_E_TIMEOUT:
30 		return -ETIME;
31 	default:
32 		return -1;
33 	}
34 }
35 EXPORT_SYMBOL(nfc_hci_result_to_errno);
36 
37 void nfc_hci_reset_pipes(struct nfc_hci_dev *hdev)
38 {
39 	int i = 0;
40 
41 	for (i = 0; i < NFC_HCI_MAX_PIPES; i++) {
42 		hdev->pipes[i].gate = NFC_HCI_INVALID_GATE;
43 		hdev->pipes[i].dest_host = NFC_HCI_INVALID_HOST;
44 	}
45 	memset(hdev->gate2pipe, NFC_HCI_INVALID_PIPE, sizeof(hdev->gate2pipe));
46 }
47 EXPORT_SYMBOL(nfc_hci_reset_pipes);
48 
49 void nfc_hci_reset_pipes_per_host(struct nfc_hci_dev *hdev, u8 host)
50 {
51 	int i = 0;
52 
53 	for (i = 0; i < NFC_HCI_MAX_PIPES; i++) {
54 		if (hdev->pipes[i].dest_host != host)
55 			continue;
56 
57 		hdev->pipes[i].gate = NFC_HCI_INVALID_GATE;
58 		hdev->pipes[i].dest_host = NFC_HCI_INVALID_HOST;
59 	}
60 }
61 EXPORT_SYMBOL(nfc_hci_reset_pipes_per_host);
62 
63 static void nfc_hci_msg_tx_work(struct work_struct *work)
64 {
65 	struct nfc_hci_dev *hdev = container_of(work, struct nfc_hci_dev,
66 						msg_tx_work);
67 	struct hci_msg *msg;
68 	struct sk_buff *skb;
69 	int r = 0;
70 
71 	mutex_lock(&hdev->msg_tx_mutex);
72 	if (hdev->shutting_down)
73 		goto exit;
74 
75 	if (hdev->cmd_pending_msg) {
76 		if (timer_pending(&hdev->cmd_timer) == 0) {
77 			if (hdev->cmd_pending_msg->cb)
78 				hdev->cmd_pending_msg->cb(hdev->
79 							  cmd_pending_msg->
80 							  cb_context,
81 							  NULL,
82 							  -ETIME);
83 			kfree(hdev->cmd_pending_msg);
84 			hdev->cmd_pending_msg = NULL;
85 		} else {
86 			goto exit;
87 		}
88 	}
89 
90 next_msg:
91 	if (list_empty(&hdev->msg_tx_queue))
92 		goto exit;
93 
94 	msg = list_first_entry(&hdev->msg_tx_queue, struct hci_msg, msg_l);
95 	list_del(&msg->msg_l);
96 
97 	pr_debug("msg_tx_queue has a cmd to send\n");
98 	while ((skb = skb_dequeue(&msg->msg_frags)) != NULL) {
99 		r = nfc_llc_xmit_from_hci(hdev->llc, skb);
100 		if (r < 0) {
101 			kfree_skb(skb);
102 			skb_queue_purge(&msg->msg_frags);
103 			if (msg->cb)
104 				msg->cb(msg->cb_context, NULL, r);
105 			kfree(msg);
106 			break;
107 		}
108 	}
109 
110 	if (r)
111 		goto next_msg;
112 
113 	if (msg->wait_response == false) {
114 		kfree(msg);
115 		goto next_msg;
116 	}
117 
118 	hdev->cmd_pending_msg = msg;
119 	mod_timer(&hdev->cmd_timer, jiffies +
120 		  msecs_to_jiffies(hdev->cmd_pending_msg->completion_delay));
121 
122 exit:
123 	mutex_unlock(&hdev->msg_tx_mutex);
124 }
125 
126 static void nfc_hci_msg_rx_work(struct work_struct *work)
127 {
128 	struct nfc_hci_dev *hdev = container_of(work, struct nfc_hci_dev,
129 						msg_rx_work);
130 	struct sk_buff *skb;
131 	struct hcp_message *message;
132 	u8 pipe;
133 	u8 type;
134 	u8 instruction;
135 
136 	while ((skb = skb_dequeue(&hdev->msg_rx_queue)) != NULL) {
137 		pipe = skb->data[0];
138 		skb_pull(skb, NFC_HCI_HCP_PACKET_HEADER_LEN);
139 		message = (struct hcp_message *)skb->data;
140 		type = HCP_MSG_GET_TYPE(message->header);
141 		instruction = HCP_MSG_GET_CMD(message->header);
142 		skb_pull(skb, NFC_HCI_HCP_MESSAGE_HEADER_LEN);
143 
144 		nfc_hci_hcp_message_rx(hdev, pipe, type, instruction, skb);
145 	}
146 }
147 
148 static void __nfc_hci_cmd_completion(struct nfc_hci_dev *hdev, int err,
149 				     struct sk_buff *skb)
150 {
151 	del_timer_sync(&hdev->cmd_timer);
152 
153 	if (hdev->cmd_pending_msg->cb)
154 		hdev->cmd_pending_msg->cb(hdev->cmd_pending_msg->cb_context,
155 					  skb, err);
156 	else
157 		kfree_skb(skb);
158 
159 	kfree(hdev->cmd_pending_msg);
160 	hdev->cmd_pending_msg = NULL;
161 
162 	schedule_work(&hdev->msg_tx_work);
163 }
164 
165 void nfc_hci_resp_received(struct nfc_hci_dev *hdev, u8 result,
166 			   struct sk_buff *skb)
167 {
168 	mutex_lock(&hdev->msg_tx_mutex);
169 
170 	if (hdev->cmd_pending_msg == NULL) {
171 		kfree_skb(skb);
172 		goto exit;
173 	}
174 
175 	__nfc_hci_cmd_completion(hdev, nfc_hci_result_to_errno(result), skb);
176 
177 exit:
178 	mutex_unlock(&hdev->msg_tx_mutex);
179 }
180 
181 void nfc_hci_cmd_received(struct nfc_hci_dev *hdev, u8 pipe, u8 cmd,
182 			  struct sk_buff *skb)
183 {
184 	u8 gate = hdev->pipes[pipe].gate;
185 	u8 status = NFC_HCI_ANY_OK;
186 	struct hci_create_pipe_resp *create_info;
187 	struct hci_delete_pipe_noti *delete_info;
188 	struct hci_all_pipe_cleared_noti *cleared_info;
189 
190 	pr_debug("from gate %x pipe %x cmd %x\n", gate, pipe, cmd);
191 
192 	switch (cmd) {
193 	case NFC_HCI_ADM_NOTIFY_PIPE_CREATED:
194 		if (skb->len != 5) {
195 			status = NFC_HCI_ANY_E_NOK;
196 			goto exit;
197 		}
198 		create_info = (struct hci_create_pipe_resp *)skb->data;
199 
200 		if (create_info->pipe >= NFC_HCI_MAX_PIPES) {
201 			status = NFC_HCI_ANY_E_NOK;
202 			goto exit;
203 		}
204 
205 		/* Save the new created pipe and bind with local gate,
206 		 * the description for skb->data[3] is destination gate id
207 		 * but since we received this cmd from host controller, we
208 		 * are the destination and it is our local gate
209 		 */
210 		hdev->gate2pipe[create_info->dest_gate] = create_info->pipe;
211 		hdev->pipes[create_info->pipe].gate = create_info->dest_gate;
212 		hdev->pipes[create_info->pipe].dest_host =
213 							create_info->src_host;
214 		break;
215 	case NFC_HCI_ANY_OPEN_PIPE:
216 		if (gate == NFC_HCI_INVALID_GATE) {
217 			status = NFC_HCI_ANY_E_NOK;
218 			goto exit;
219 		}
220 		break;
221 	case NFC_HCI_ADM_NOTIFY_PIPE_DELETED:
222 		if (skb->len != 1) {
223 			status = NFC_HCI_ANY_E_NOK;
224 			goto exit;
225 		}
226 		delete_info = (struct hci_delete_pipe_noti *)skb->data;
227 
228 		if (delete_info->pipe >= NFC_HCI_MAX_PIPES) {
229 			status = NFC_HCI_ANY_E_NOK;
230 			goto exit;
231 		}
232 
233 		hdev->pipes[delete_info->pipe].gate = NFC_HCI_INVALID_GATE;
234 		hdev->pipes[delete_info->pipe].dest_host = NFC_HCI_INVALID_HOST;
235 		break;
236 	case NFC_HCI_ADM_NOTIFY_ALL_PIPE_CLEARED:
237 		if (skb->len != 1) {
238 			status = NFC_HCI_ANY_E_NOK;
239 			goto exit;
240 		}
241 		cleared_info = (struct hci_all_pipe_cleared_noti *)skb->data;
242 
243 		nfc_hci_reset_pipes_per_host(hdev, cleared_info->host);
244 		break;
245 	default:
246 		pr_info("Discarded unknown cmd %x to gate %x\n", cmd, gate);
247 		break;
248 	}
249 
250 	if (hdev->ops->cmd_received)
251 		hdev->ops->cmd_received(hdev, pipe, cmd, skb);
252 
253 exit:
254 	nfc_hci_hcp_message_tx(hdev, pipe, NFC_HCI_HCP_RESPONSE,
255 			       status, NULL, 0, NULL, NULL, 0);
256 
257 	kfree_skb(skb);
258 }
259 
260 u32 nfc_hci_sak_to_protocol(u8 sak)
261 {
262 	switch (NFC_HCI_TYPE_A_SEL_PROT(sak)) {
263 	case NFC_HCI_TYPE_A_SEL_PROT_MIFARE:
264 		return NFC_PROTO_MIFARE_MASK;
265 	case NFC_HCI_TYPE_A_SEL_PROT_ISO14443:
266 		return NFC_PROTO_ISO14443_MASK;
267 	case NFC_HCI_TYPE_A_SEL_PROT_DEP:
268 		return NFC_PROTO_NFC_DEP_MASK;
269 	case NFC_HCI_TYPE_A_SEL_PROT_ISO14443_DEP:
270 		return NFC_PROTO_ISO14443_MASK | NFC_PROTO_NFC_DEP_MASK;
271 	default:
272 		return 0xffffffff;
273 	}
274 }
275 EXPORT_SYMBOL(nfc_hci_sak_to_protocol);
276 
277 int nfc_hci_target_discovered(struct nfc_hci_dev *hdev, u8 gate)
278 {
279 	struct nfc_target *targets;
280 	struct sk_buff *atqa_skb = NULL;
281 	struct sk_buff *sak_skb = NULL;
282 	struct sk_buff *uid_skb = NULL;
283 	int r;
284 
285 	pr_debug("from gate %d\n", gate);
286 
287 	targets = kzalloc(sizeof(struct nfc_target), GFP_KERNEL);
288 	if (targets == NULL)
289 		return -ENOMEM;
290 
291 	switch (gate) {
292 	case NFC_HCI_RF_READER_A_GATE:
293 		r = nfc_hci_get_param(hdev, NFC_HCI_RF_READER_A_GATE,
294 				      NFC_HCI_RF_READER_A_ATQA, &atqa_skb);
295 		if (r < 0)
296 			goto exit;
297 
298 		r = nfc_hci_get_param(hdev, NFC_HCI_RF_READER_A_GATE,
299 				      NFC_HCI_RF_READER_A_SAK, &sak_skb);
300 		if (r < 0)
301 			goto exit;
302 
303 		if (atqa_skb->len != 2 || sak_skb->len != 1) {
304 			r = -EPROTO;
305 			goto exit;
306 		}
307 
308 		targets->supported_protocols =
309 				nfc_hci_sak_to_protocol(sak_skb->data[0]);
310 		if (targets->supported_protocols == 0xffffffff) {
311 			r = -EPROTO;
312 			goto exit;
313 		}
314 
315 		targets->sens_res = be16_to_cpu(*(__be16 *)atqa_skb->data);
316 		targets->sel_res = sak_skb->data[0];
317 
318 		r = nfc_hci_get_param(hdev, NFC_HCI_RF_READER_A_GATE,
319 				      NFC_HCI_RF_READER_A_UID, &uid_skb);
320 		if (r < 0)
321 			goto exit;
322 
323 		if (uid_skb->len == 0 || uid_skb->len > NFC_NFCID1_MAXSIZE) {
324 			r = -EPROTO;
325 			goto exit;
326 		}
327 
328 		memcpy(targets->nfcid1, uid_skb->data, uid_skb->len);
329 		targets->nfcid1_len = uid_skb->len;
330 
331 		if (hdev->ops->complete_target_discovered) {
332 			r = hdev->ops->complete_target_discovered(hdev, gate,
333 								  targets);
334 			if (r < 0)
335 				goto exit;
336 		}
337 		break;
338 	case NFC_HCI_RF_READER_B_GATE:
339 		targets->supported_protocols = NFC_PROTO_ISO14443_B_MASK;
340 		break;
341 	default:
342 		if (hdev->ops->target_from_gate)
343 			r = hdev->ops->target_from_gate(hdev, gate, targets);
344 		else
345 			r = -EPROTO;
346 		if (r < 0)
347 			goto exit;
348 
349 		if (hdev->ops->complete_target_discovered) {
350 			r = hdev->ops->complete_target_discovered(hdev, gate,
351 								  targets);
352 			if (r < 0)
353 				goto exit;
354 		}
355 		break;
356 	}
357 
358 	/* if driver set the new gate, we will skip the old one */
359 	if (targets->hci_reader_gate == 0x00)
360 		targets->hci_reader_gate = gate;
361 
362 	r = nfc_targets_found(hdev->ndev, targets, 1);
363 
364 exit:
365 	kfree(targets);
366 	kfree_skb(atqa_skb);
367 	kfree_skb(sak_skb);
368 	kfree_skb(uid_skb);
369 
370 	return r;
371 }
372 EXPORT_SYMBOL(nfc_hci_target_discovered);
373 
374 void nfc_hci_event_received(struct nfc_hci_dev *hdev, u8 pipe, u8 event,
375 			    struct sk_buff *skb)
376 {
377 	int r = 0;
378 	u8 gate = hdev->pipes[pipe].gate;
379 
380 	if (gate == NFC_HCI_INVALID_GATE) {
381 		pr_err("Discarded event %x to unopened pipe %x\n", event, pipe);
382 		goto exit;
383 	}
384 
385 	if (hdev->ops->event_received) {
386 		r = hdev->ops->event_received(hdev, pipe, event, skb);
387 		if (r <= 0)
388 			goto exit_noskb;
389 	}
390 
391 	switch (event) {
392 	case NFC_HCI_EVT_TARGET_DISCOVERED:
393 		if (skb->len < 1) {	/* no status data? */
394 			r = -EPROTO;
395 			goto exit;
396 		}
397 
398 		if (skb->data[0] == 3) {
399 			/* TODO: Multiple targets in field, none activated
400 			 * poll is supposedly stopped, but there is no
401 			 * single target to activate, so nothing to report
402 			 * up.
403 			 * if we need to restart poll, we must save the
404 			 * protocols from the initial poll and reuse here.
405 			 */
406 		}
407 
408 		if (skb->data[0] != 0) {
409 			r = -EPROTO;
410 			goto exit;
411 		}
412 
413 		r = nfc_hci_target_discovered(hdev, gate);
414 		break;
415 	default:
416 		pr_info("Discarded unknown event %x to gate %x\n", event, gate);
417 		r = -EINVAL;
418 		break;
419 	}
420 
421 exit:
422 	kfree_skb(skb);
423 
424 exit_noskb:
425 	if (r)
426 		nfc_hci_driver_failure(hdev, r);
427 }
428 
429 static void nfc_hci_cmd_timeout(struct timer_list *t)
430 {
431 	struct nfc_hci_dev *hdev = from_timer(hdev, t, cmd_timer);
432 
433 	schedule_work(&hdev->msg_tx_work);
434 }
435 
436 static int hci_dev_connect_gates(struct nfc_hci_dev *hdev, u8 gate_count,
437 				 struct nfc_hci_gate *gates)
438 {
439 	int r;
440 	while (gate_count--) {
441 		r = nfc_hci_connect_gate(hdev, NFC_HCI_HOST_CONTROLLER_ID,
442 					 gates->gate, gates->pipe);
443 		if (r < 0)
444 			return r;
445 		gates++;
446 	}
447 
448 	return 0;
449 }
450 
451 static int hci_dev_session_init(struct nfc_hci_dev *hdev)
452 {
453 	struct sk_buff *skb = NULL;
454 	int r;
455 
456 	if (hdev->init_data.gates[0].gate != NFC_HCI_ADMIN_GATE)
457 		return -EPROTO;
458 
459 	r = nfc_hci_connect_gate(hdev, NFC_HCI_HOST_CONTROLLER_ID,
460 				 hdev->init_data.gates[0].gate,
461 				 hdev->init_data.gates[0].pipe);
462 	if (r < 0)
463 		goto exit;
464 
465 	r = nfc_hci_get_param(hdev, NFC_HCI_ADMIN_GATE,
466 			      NFC_HCI_ADMIN_SESSION_IDENTITY, &skb);
467 	if (r < 0)
468 		goto disconnect_all;
469 
470 	if (skb->len && skb->len == strlen(hdev->init_data.session_id) &&
471 		(memcmp(hdev->init_data.session_id, skb->data,
472 			   skb->len) == 0) && hdev->ops->load_session) {
473 		/* Restore gate<->pipe table from some proprietary location. */
474 
475 		r = hdev->ops->load_session(hdev);
476 
477 		if (r < 0)
478 			goto disconnect_all;
479 	} else {
480 
481 		r = nfc_hci_disconnect_all_gates(hdev);
482 		if (r < 0)
483 			goto exit;
484 
485 		r = hci_dev_connect_gates(hdev, hdev->init_data.gate_count,
486 					  hdev->init_data.gates);
487 		if (r < 0)
488 			goto disconnect_all;
489 
490 		r = nfc_hci_set_param(hdev, NFC_HCI_ADMIN_GATE,
491 				NFC_HCI_ADMIN_SESSION_IDENTITY,
492 				hdev->init_data.session_id,
493 				strlen(hdev->init_data.session_id));
494 	}
495 	if (r == 0)
496 		goto exit;
497 
498 disconnect_all:
499 	nfc_hci_disconnect_all_gates(hdev);
500 
501 exit:
502 	kfree_skb(skb);
503 
504 	return r;
505 }
506 
507 static int hci_dev_version(struct nfc_hci_dev *hdev)
508 {
509 	int r;
510 	struct sk_buff *skb;
511 
512 	r = nfc_hci_get_param(hdev, NFC_HCI_ID_MGMT_GATE,
513 			      NFC_HCI_ID_MGMT_VERSION_SW, &skb);
514 	if (r == -EOPNOTSUPP) {
515 		pr_info("Software/Hardware info not available\n");
516 		return 0;
517 	}
518 	if (r < 0)
519 		return r;
520 
521 	if (skb->len != 3) {
522 		kfree_skb(skb);
523 		return -EINVAL;
524 	}
525 
526 	hdev->sw_romlib = (skb->data[0] & 0xf0) >> 4;
527 	hdev->sw_patch = skb->data[0] & 0x0f;
528 	hdev->sw_flashlib_major = skb->data[1];
529 	hdev->sw_flashlib_minor = skb->data[2];
530 
531 	kfree_skb(skb);
532 
533 	r = nfc_hci_get_param(hdev, NFC_HCI_ID_MGMT_GATE,
534 			      NFC_HCI_ID_MGMT_VERSION_HW, &skb);
535 	if (r < 0)
536 		return r;
537 
538 	if (skb->len != 3) {
539 		kfree_skb(skb);
540 		return -EINVAL;
541 	}
542 
543 	hdev->hw_derivative = (skb->data[0] & 0xe0) >> 5;
544 	hdev->hw_version = skb->data[0] & 0x1f;
545 	hdev->hw_mpw = (skb->data[1] & 0xc0) >> 6;
546 	hdev->hw_software = skb->data[1] & 0x3f;
547 	hdev->hw_bsid = skb->data[2];
548 
549 	kfree_skb(skb);
550 
551 	pr_info("SOFTWARE INFO:\n");
552 	pr_info("RomLib         : %d\n", hdev->sw_romlib);
553 	pr_info("Patch          : %d\n", hdev->sw_patch);
554 	pr_info("FlashLib Major : %d\n", hdev->sw_flashlib_major);
555 	pr_info("FlashLib Minor : %d\n", hdev->sw_flashlib_minor);
556 	pr_info("HARDWARE INFO:\n");
557 	pr_info("Derivative     : %d\n", hdev->hw_derivative);
558 	pr_info("HW Version     : %d\n", hdev->hw_version);
559 	pr_info("#MPW           : %d\n", hdev->hw_mpw);
560 	pr_info("Software       : %d\n", hdev->hw_software);
561 	pr_info("BSID Version   : %d\n", hdev->hw_bsid);
562 
563 	return 0;
564 }
565 
566 static int hci_dev_up(struct nfc_dev *nfc_dev)
567 {
568 	struct nfc_hci_dev *hdev = nfc_get_drvdata(nfc_dev);
569 	int r = 0;
570 
571 	if (hdev->ops->open) {
572 		r = hdev->ops->open(hdev);
573 		if (r < 0)
574 			return r;
575 	}
576 
577 	r = nfc_llc_start(hdev->llc);
578 	if (r < 0)
579 		goto exit_close;
580 
581 	r = hci_dev_session_init(hdev);
582 	if (r < 0)
583 		goto exit_llc;
584 
585 	r = nfc_hci_send_event(hdev, NFC_HCI_RF_READER_A_GATE,
586 			       NFC_HCI_EVT_END_OPERATION, NULL, 0);
587 	if (r < 0)
588 		goto exit_llc;
589 
590 	if (hdev->ops->hci_ready) {
591 		r = hdev->ops->hci_ready(hdev);
592 		if (r < 0)
593 			goto exit_llc;
594 	}
595 
596 	r = hci_dev_version(hdev);
597 	if (r < 0)
598 		goto exit_llc;
599 
600 	return 0;
601 
602 exit_llc:
603 	nfc_llc_stop(hdev->llc);
604 
605 exit_close:
606 	if (hdev->ops->close)
607 		hdev->ops->close(hdev);
608 
609 	return r;
610 }
611 
612 static int hci_dev_down(struct nfc_dev *nfc_dev)
613 {
614 	struct nfc_hci_dev *hdev = nfc_get_drvdata(nfc_dev);
615 
616 	nfc_llc_stop(hdev->llc);
617 
618 	if (hdev->ops->close)
619 		hdev->ops->close(hdev);
620 
621 	nfc_hci_reset_pipes(hdev);
622 
623 	return 0;
624 }
625 
626 static int hci_start_poll(struct nfc_dev *nfc_dev,
627 			  u32 im_protocols, u32 tm_protocols)
628 {
629 	struct nfc_hci_dev *hdev = nfc_get_drvdata(nfc_dev);
630 
631 	if (hdev->ops->start_poll)
632 		return hdev->ops->start_poll(hdev, im_protocols, tm_protocols);
633 	else
634 		return nfc_hci_send_event(hdev, NFC_HCI_RF_READER_A_GATE,
635 					  NFC_HCI_EVT_READER_REQUESTED,
636 					  NULL, 0);
637 }
638 
639 static void hci_stop_poll(struct nfc_dev *nfc_dev)
640 {
641 	struct nfc_hci_dev *hdev = nfc_get_drvdata(nfc_dev);
642 
643 	if (hdev->ops->stop_poll)
644 		hdev->ops->stop_poll(hdev);
645 	else
646 		nfc_hci_send_event(hdev, NFC_HCI_RF_READER_A_GATE,
647 				   NFC_HCI_EVT_END_OPERATION, NULL, 0);
648 }
649 
650 static int hci_dep_link_up(struct nfc_dev *nfc_dev, struct nfc_target *target,
651 				__u8 comm_mode, __u8 *gb, size_t gb_len)
652 {
653 	struct nfc_hci_dev *hdev = nfc_get_drvdata(nfc_dev);
654 
655 	if (!hdev->ops->dep_link_up)
656 		return 0;
657 
658 	return hdev->ops->dep_link_up(hdev, target, comm_mode,
659 				      gb, gb_len);
660 }
661 
662 static int hci_dep_link_down(struct nfc_dev *nfc_dev)
663 {
664 	struct nfc_hci_dev *hdev = nfc_get_drvdata(nfc_dev);
665 
666 	if (!hdev->ops->dep_link_down)
667 		return 0;
668 
669 	return hdev->ops->dep_link_down(hdev);
670 }
671 
672 static int hci_activate_target(struct nfc_dev *nfc_dev,
673 			       struct nfc_target *target, u32 protocol)
674 {
675 	return 0;
676 }
677 
678 static void hci_deactivate_target(struct nfc_dev *nfc_dev,
679 				  struct nfc_target *target,
680 				  u8 mode)
681 {
682 }
683 
684 #define HCI_CB_TYPE_TRANSCEIVE 1
685 
686 static void hci_transceive_cb(void *context, struct sk_buff *skb, int err)
687 {
688 	struct nfc_hci_dev *hdev = context;
689 
690 	switch (hdev->async_cb_type) {
691 	case HCI_CB_TYPE_TRANSCEIVE:
692 		/*
693 		 * TODO: Check RF Error indicator to make sure data is valid.
694 		 * It seems that HCI cmd can complete without error, but data
695 		 * can be invalid if an RF error occured? Ignore for now.
696 		 */
697 		if (err == 0)
698 			skb_trim(skb, skb->len - 1); /* RF Err ind */
699 
700 		hdev->async_cb(hdev->async_cb_context, skb, err);
701 		break;
702 	default:
703 		if (err == 0)
704 			kfree_skb(skb);
705 		break;
706 	}
707 }
708 
709 static int hci_transceive(struct nfc_dev *nfc_dev, struct nfc_target *target,
710 			  struct sk_buff *skb, data_exchange_cb_t cb,
711 			  void *cb_context)
712 {
713 	struct nfc_hci_dev *hdev = nfc_get_drvdata(nfc_dev);
714 	int r;
715 
716 	pr_debug("target_idx=%d\n", target->idx);
717 
718 	switch (target->hci_reader_gate) {
719 	case NFC_HCI_RF_READER_A_GATE:
720 	case NFC_HCI_RF_READER_B_GATE:
721 		if (hdev->ops->im_transceive) {
722 			r = hdev->ops->im_transceive(hdev, target, skb, cb,
723 						     cb_context);
724 			if (r <= 0)	/* handled */
725 				break;
726 		}
727 
728 		*(u8 *)skb_push(skb, 1) = 0;	/* CTR, see spec:10.2.2.1 */
729 
730 		hdev->async_cb_type = HCI_CB_TYPE_TRANSCEIVE;
731 		hdev->async_cb = cb;
732 		hdev->async_cb_context = cb_context;
733 
734 		r = nfc_hci_send_cmd_async(hdev, target->hci_reader_gate,
735 					   NFC_HCI_WR_XCHG_DATA, skb->data,
736 					   skb->len, hci_transceive_cb, hdev);
737 		break;
738 	default:
739 		if (hdev->ops->im_transceive) {
740 			r = hdev->ops->im_transceive(hdev, target, skb, cb,
741 						     cb_context);
742 			if (r == 1)
743 				r = -ENOTSUPP;
744 		} else {
745 			r = -ENOTSUPP;
746 		}
747 		break;
748 	}
749 
750 	kfree_skb(skb);
751 
752 	return r;
753 }
754 
755 static int hci_tm_send(struct nfc_dev *nfc_dev, struct sk_buff *skb)
756 {
757 	struct nfc_hci_dev *hdev = nfc_get_drvdata(nfc_dev);
758 
759 	if (!hdev->ops->tm_send) {
760 		kfree_skb(skb);
761 		return -ENOTSUPP;
762 	}
763 
764 	return hdev->ops->tm_send(hdev, skb);
765 }
766 
767 static int hci_check_presence(struct nfc_dev *nfc_dev,
768 			      struct nfc_target *target)
769 {
770 	struct nfc_hci_dev *hdev = nfc_get_drvdata(nfc_dev);
771 
772 	if (!hdev->ops->check_presence)
773 		return 0;
774 
775 	return hdev->ops->check_presence(hdev, target);
776 }
777 
778 static int hci_discover_se(struct nfc_dev *nfc_dev)
779 {
780 	struct nfc_hci_dev *hdev = nfc_get_drvdata(nfc_dev);
781 
782 	if (hdev->ops->discover_se)
783 		return hdev->ops->discover_se(hdev);
784 
785 	return 0;
786 }
787 
788 static int hci_enable_se(struct nfc_dev *nfc_dev, u32 se_idx)
789 {
790 	struct nfc_hci_dev *hdev = nfc_get_drvdata(nfc_dev);
791 
792 	if (hdev->ops->enable_se)
793 		return hdev->ops->enable_se(hdev, se_idx);
794 
795 	return 0;
796 }
797 
798 static int hci_disable_se(struct nfc_dev *nfc_dev, u32 se_idx)
799 {
800 	struct nfc_hci_dev *hdev = nfc_get_drvdata(nfc_dev);
801 
802 	if (hdev->ops->disable_se)
803 		return hdev->ops->disable_se(hdev, se_idx);
804 
805 	return 0;
806 }
807 
808 static int hci_se_io(struct nfc_dev *nfc_dev, u32 se_idx,
809 		     u8 *apdu, size_t apdu_length,
810 		     se_io_cb_t cb, void *cb_context)
811 {
812 	struct nfc_hci_dev *hdev = nfc_get_drvdata(nfc_dev);
813 
814 	if (hdev->ops->se_io)
815 		return hdev->ops->se_io(hdev, se_idx, apdu,
816 					apdu_length, cb, cb_context);
817 
818 	return 0;
819 }
820 
821 static void nfc_hci_failure(struct nfc_hci_dev *hdev, int err)
822 {
823 	mutex_lock(&hdev->msg_tx_mutex);
824 
825 	if (hdev->cmd_pending_msg == NULL) {
826 		nfc_driver_failure(hdev->ndev, err);
827 		goto exit;
828 	}
829 
830 	__nfc_hci_cmd_completion(hdev, err, NULL);
831 
832 exit:
833 	mutex_unlock(&hdev->msg_tx_mutex);
834 }
835 
836 static void nfc_hci_llc_failure(struct nfc_hci_dev *hdev, int err)
837 {
838 	nfc_hci_failure(hdev, err);
839 }
840 
841 static void nfc_hci_recv_from_llc(struct nfc_hci_dev *hdev, struct sk_buff *skb)
842 {
843 	struct hcp_packet *packet;
844 	u8 type;
845 	u8 instruction;
846 	struct sk_buff *hcp_skb;
847 	u8 pipe;
848 	struct sk_buff *frag_skb;
849 	int msg_len;
850 
851 	packet = (struct hcp_packet *)skb->data;
852 	if ((packet->header & ~NFC_HCI_FRAGMENT) == 0) {
853 		skb_queue_tail(&hdev->rx_hcp_frags, skb);
854 		return;
855 	}
856 
857 	/* it's the last fragment. Does it need re-aggregation? */
858 	if (skb_queue_len(&hdev->rx_hcp_frags)) {
859 		pipe = packet->header & NFC_HCI_FRAGMENT;
860 		skb_queue_tail(&hdev->rx_hcp_frags, skb);
861 
862 		msg_len = 0;
863 		skb_queue_walk(&hdev->rx_hcp_frags, frag_skb) {
864 			msg_len += (frag_skb->len -
865 				    NFC_HCI_HCP_PACKET_HEADER_LEN);
866 		}
867 
868 		hcp_skb = nfc_alloc_recv_skb(NFC_HCI_HCP_PACKET_HEADER_LEN +
869 					     msg_len, GFP_KERNEL);
870 		if (hcp_skb == NULL) {
871 			nfc_hci_failure(hdev, -ENOMEM);
872 			return;
873 		}
874 
875 		skb_put_u8(hcp_skb, pipe);
876 
877 		skb_queue_walk(&hdev->rx_hcp_frags, frag_skb) {
878 			msg_len = frag_skb->len - NFC_HCI_HCP_PACKET_HEADER_LEN;
879 			skb_put_data(hcp_skb,
880 				     frag_skb->data + NFC_HCI_HCP_PACKET_HEADER_LEN,
881 				     msg_len);
882 		}
883 
884 		skb_queue_purge(&hdev->rx_hcp_frags);
885 	} else {
886 		packet->header &= NFC_HCI_FRAGMENT;
887 		hcp_skb = skb;
888 	}
889 
890 	/* if this is a response, dispatch immediately to
891 	 * unblock waiting cmd context. Otherwise, enqueue to dispatch
892 	 * in separate context where handler can also execute command.
893 	 */
894 	packet = (struct hcp_packet *)hcp_skb->data;
895 	type = HCP_MSG_GET_TYPE(packet->message.header);
896 	if (type == NFC_HCI_HCP_RESPONSE) {
897 		pipe = packet->header;
898 		instruction = HCP_MSG_GET_CMD(packet->message.header);
899 		skb_pull(hcp_skb, NFC_HCI_HCP_PACKET_HEADER_LEN +
900 			 NFC_HCI_HCP_MESSAGE_HEADER_LEN);
901 		nfc_hci_hcp_message_rx(hdev, pipe, type, instruction, hcp_skb);
902 	} else {
903 		skb_queue_tail(&hdev->msg_rx_queue, hcp_skb);
904 		schedule_work(&hdev->msg_rx_work);
905 	}
906 }
907 
908 static int hci_fw_download(struct nfc_dev *nfc_dev, const char *firmware_name)
909 {
910 	struct nfc_hci_dev *hdev = nfc_get_drvdata(nfc_dev);
911 
912 	if (!hdev->ops->fw_download)
913 		return -ENOTSUPP;
914 
915 	return hdev->ops->fw_download(hdev, firmware_name);
916 }
917 
918 static struct nfc_ops hci_nfc_ops = {
919 	.dev_up = hci_dev_up,
920 	.dev_down = hci_dev_down,
921 	.start_poll = hci_start_poll,
922 	.stop_poll = hci_stop_poll,
923 	.dep_link_up = hci_dep_link_up,
924 	.dep_link_down = hci_dep_link_down,
925 	.activate_target = hci_activate_target,
926 	.deactivate_target = hci_deactivate_target,
927 	.im_transceive = hci_transceive,
928 	.tm_send = hci_tm_send,
929 	.check_presence = hci_check_presence,
930 	.fw_download = hci_fw_download,
931 	.discover_se = hci_discover_se,
932 	.enable_se = hci_enable_se,
933 	.disable_se = hci_disable_se,
934 	.se_io = hci_se_io,
935 };
936 
937 struct nfc_hci_dev *nfc_hci_allocate_device(struct nfc_hci_ops *ops,
938 					    struct nfc_hci_init_data *init_data,
939 					    unsigned long quirks,
940 					    u32 protocols,
941 					    const char *llc_name,
942 					    int tx_headroom,
943 					    int tx_tailroom,
944 					    int max_link_payload)
945 {
946 	struct nfc_hci_dev *hdev;
947 
948 	if (ops->xmit == NULL)
949 		return NULL;
950 
951 	if (protocols == 0)
952 		return NULL;
953 
954 	hdev = kzalloc(sizeof(struct nfc_hci_dev), GFP_KERNEL);
955 	if (hdev == NULL)
956 		return NULL;
957 
958 	hdev->llc = nfc_llc_allocate(llc_name, hdev, ops->xmit,
959 				     nfc_hci_recv_from_llc, tx_headroom,
960 				     tx_tailroom, nfc_hci_llc_failure);
961 	if (hdev->llc == NULL) {
962 		kfree(hdev);
963 		return NULL;
964 	}
965 
966 	hdev->ndev = nfc_allocate_device(&hci_nfc_ops, protocols,
967 					 tx_headroom + HCI_CMDS_HEADROOM,
968 					 tx_tailroom);
969 	if (!hdev->ndev) {
970 		nfc_llc_free(hdev->llc);
971 		kfree(hdev);
972 		return NULL;
973 	}
974 
975 	hdev->ops = ops;
976 	hdev->max_data_link_payload = max_link_payload;
977 	hdev->init_data = *init_data;
978 
979 	nfc_set_drvdata(hdev->ndev, hdev);
980 
981 	nfc_hci_reset_pipes(hdev);
982 
983 	hdev->quirks = quirks;
984 
985 	return hdev;
986 }
987 EXPORT_SYMBOL(nfc_hci_allocate_device);
988 
989 void nfc_hci_free_device(struct nfc_hci_dev *hdev)
990 {
991 	nfc_free_device(hdev->ndev);
992 	nfc_llc_free(hdev->llc);
993 	kfree(hdev);
994 }
995 EXPORT_SYMBOL(nfc_hci_free_device);
996 
997 int nfc_hci_register_device(struct nfc_hci_dev *hdev)
998 {
999 	mutex_init(&hdev->msg_tx_mutex);
1000 
1001 	INIT_LIST_HEAD(&hdev->msg_tx_queue);
1002 
1003 	INIT_WORK(&hdev->msg_tx_work, nfc_hci_msg_tx_work);
1004 
1005 	timer_setup(&hdev->cmd_timer, nfc_hci_cmd_timeout, 0);
1006 
1007 	skb_queue_head_init(&hdev->rx_hcp_frags);
1008 
1009 	INIT_WORK(&hdev->msg_rx_work, nfc_hci_msg_rx_work);
1010 
1011 	skb_queue_head_init(&hdev->msg_rx_queue);
1012 
1013 	return nfc_register_device(hdev->ndev);
1014 }
1015 EXPORT_SYMBOL(nfc_hci_register_device);
1016 
1017 void nfc_hci_unregister_device(struct nfc_hci_dev *hdev)
1018 {
1019 	struct hci_msg *msg, *n;
1020 
1021 	mutex_lock(&hdev->msg_tx_mutex);
1022 
1023 	if (hdev->cmd_pending_msg) {
1024 		if (hdev->cmd_pending_msg->cb)
1025 			hdev->cmd_pending_msg->cb(
1026 					     hdev->cmd_pending_msg->cb_context,
1027 					     NULL, -ESHUTDOWN);
1028 		kfree(hdev->cmd_pending_msg);
1029 		hdev->cmd_pending_msg = NULL;
1030 	}
1031 
1032 	hdev->shutting_down = true;
1033 
1034 	mutex_unlock(&hdev->msg_tx_mutex);
1035 
1036 	del_timer_sync(&hdev->cmd_timer);
1037 	cancel_work_sync(&hdev->msg_tx_work);
1038 
1039 	cancel_work_sync(&hdev->msg_rx_work);
1040 
1041 	nfc_unregister_device(hdev->ndev);
1042 
1043 	skb_queue_purge(&hdev->rx_hcp_frags);
1044 	skb_queue_purge(&hdev->msg_rx_queue);
1045 
1046 	list_for_each_entry_safe(msg, n, &hdev->msg_tx_queue, msg_l) {
1047 		list_del(&msg->msg_l);
1048 		skb_queue_purge(&msg->msg_frags);
1049 		kfree(msg);
1050 	}
1051 }
1052 EXPORT_SYMBOL(nfc_hci_unregister_device);
1053 
1054 void nfc_hci_set_clientdata(struct nfc_hci_dev *hdev, void *clientdata)
1055 {
1056 	hdev->clientdata = clientdata;
1057 }
1058 EXPORT_SYMBOL(nfc_hci_set_clientdata);
1059 
1060 void *nfc_hci_get_clientdata(struct nfc_hci_dev *hdev)
1061 {
1062 	return hdev->clientdata;
1063 }
1064 EXPORT_SYMBOL(nfc_hci_get_clientdata);
1065 
1066 void nfc_hci_driver_failure(struct nfc_hci_dev *hdev, int err)
1067 {
1068 	nfc_hci_failure(hdev, err);
1069 }
1070 EXPORT_SYMBOL(nfc_hci_driver_failure);
1071 
1072 void nfc_hci_recv_frame(struct nfc_hci_dev *hdev, struct sk_buff *skb)
1073 {
1074 	nfc_llc_rcv_from_drv(hdev->llc, skb);
1075 }
1076 EXPORT_SYMBOL(nfc_hci_recv_frame);
1077 
1078 static int __init nfc_hci_init(void)
1079 {
1080 	return nfc_llc_init();
1081 }
1082 
1083 static void __exit nfc_hci_exit(void)
1084 {
1085 	nfc_llc_exit();
1086 }
1087 
1088 subsys_initcall(nfc_hci_init);
1089 module_exit(nfc_hci_exit);
1090 
1091 MODULE_LICENSE("GPL");
1092 MODULE_DESCRIPTION("NFC HCI Core");
1093