xref: /linux/net/nfc/nci/hci.c (revision 63307d015b91e626c97bb82e88054af3d0b74643)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  The NFC Controller Interface is the communication protocol between an
4  *  NFC Controller (NFCC) and a Device Host (DH).
5  *  This is the HCI over NCI implementation, as specified in the 10.2
6  *  section of the NCI 1.1 specification.
7  *
8  *  Copyright (C) 2014  STMicroelectronics SAS. All rights reserved.
9  */
10 
11 #include <linux/skbuff.h>
12 
13 #include "../nfc.h"
14 #include <net/nfc/nci.h>
15 #include <net/nfc/nci_core.h>
16 #include <linux/nfc.h>
17 
18 struct nci_data {
19 	u8              conn_id;
20 	u8              pipe;
21 	u8              cmd;
22 	const u8        *data;
23 	u32             data_len;
24 } __packed;
25 
26 struct nci_hci_create_pipe_params {
27 	u8 src_gate;
28 	u8 dest_host;
29 	u8 dest_gate;
30 } __packed;
31 
32 struct nci_hci_create_pipe_resp {
33 	u8 src_host;
34 	u8 src_gate;
35 	u8 dest_host;
36 	u8 dest_gate;
37 	u8 pipe;
38 } __packed;
39 
40 struct nci_hci_delete_pipe_noti {
41 	u8 pipe;
42 } __packed;
43 
44 struct nci_hci_all_pipe_cleared_noti {
45 	u8 host;
46 } __packed;
47 
48 struct nci_hcp_message {
49 	u8 header;      /* type -cmd,evt,rsp- + instruction */
50 	u8 data[];
51 } __packed;
52 
53 struct nci_hcp_packet {
54 	u8 header;      /* cbit+pipe */
55 	struct nci_hcp_message message;
56 } __packed;
57 
58 #define NCI_HCI_ANY_SET_PARAMETER  0x01
59 #define NCI_HCI_ANY_GET_PARAMETER  0x02
60 #define NCI_HCI_ANY_CLOSE_PIPE     0x04
61 #define NCI_HCI_ADM_CLEAR_ALL_PIPE 0x14
62 
63 #define NCI_HFP_NO_CHAINING        0x80
64 
65 #define NCI_NFCEE_ID_HCI                0x80
66 
67 #define NCI_EVT_HOT_PLUG           0x03
68 
69 #define NCI_HCI_ADMIN_PARAM_SESSION_IDENTITY       0x01
70 #define NCI_HCI_ADM_CREATE_PIPE			0x10
71 #define NCI_HCI_ADM_DELETE_PIPE			0x11
72 
73 /* HCP headers */
74 #define NCI_HCI_HCP_PACKET_HEADER_LEN      1
75 #define NCI_HCI_HCP_MESSAGE_HEADER_LEN     1
76 #define NCI_HCI_HCP_HEADER_LEN             2
77 
78 /* HCP types */
79 #define NCI_HCI_HCP_COMMAND        0x00
80 #define NCI_HCI_HCP_EVENT          0x01
81 #define NCI_HCI_HCP_RESPONSE       0x02
82 
83 #define NCI_HCI_ADM_NOTIFY_PIPE_CREATED     0x12
84 #define NCI_HCI_ADM_NOTIFY_PIPE_DELETED     0x13
85 #define NCI_HCI_ADM_NOTIFY_ALL_PIPE_CLEARED 0x15
86 
87 #define NCI_HCI_FRAGMENT           0x7f
88 #define NCI_HCP_HEADER(type, instr) ((((type) & 0x03) << 6) |\
89 				      ((instr) & 0x3f))
90 
91 #define NCI_HCP_MSG_GET_TYPE(header) ((header & 0xc0) >> 6)
92 #define NCI_HCP_MSG_GET_CMD(header)  (header & 0x3f)
93 #define NCI_HCP_MSG_GET_PIPE(header) (header & 0x7f)
94 
95 static int nci_hci_result_to_errno(u8 result)
96 {
97 	switch (result) {
98 	case NCI_HCI_ANY_OK:
99 		return 0;
100 	case NCI_HCI_ANY_E_REG_PAR_UNKNOWN:
101 		return -EOPNOTSUPP;
102 	case NCI_HCI_ANY_E_TIMEOUT:
103 		return -ETIME;
104 	default:
105 		return -1;
106 	}
107 }
108 
109 /* HCI core */
110 static void nci_hci_reset_pipes(struct nci_hci_dev *hdev)
111 {
112 	int i;
113 
114 	for (i = 0; i < NCI_HCI_MAX_PIPES; i++) {
115 		hdev->pipes[i].gate = NCI_HCI_INVALID_GATE;
116 		hdev->pipes[i].host = NCI_HCI_INVALID_HOST;
117 	}
118 	memset(hdev->gate2pipe, NCI_HCI_INVALID_PIPE, sizeof(hdev->gate2pipe));
119 }
120 
121 static void nci_hci_reset_pipes_per_host(struct nci_dev *ndev, u8 host)
122 {
123 	int i;
124 
125 	for (i = 0; i < NCI_HCI_MAX_PIPES; i++) {
126 		if (ndev->hci_dev->pipes[i].host == host) {
127 			ndev->hci_dev->pipes[i].gate = NCI_HCI_INVALID_GATE;
128 			ndev->hci_dev->pipes[i].host = NCI_HCI_INVALID_HOST;
129 		}
130 	}
131 }
132 
133 /* Fragment HCI data over NCI packet.
134  * NFC Forum NCI 10.2.2 Data Exchange:
135  * The payload of the Data Packets sent on the Logical Connection SHALL be
136  * valid HCP packets, as defined within [ETSI_102622]. Each Data Packet SHALL
137  * contain a single HCP packet. NCI Segmentation and Reassembly SHALL NOT be
138  * applied to Data Messages in either direction. The HCI fragmentation mechanism
139  * is used if required.
140  */
141 static int nci_hci_send_data(struct nci_dev *ndev, u8 pipe,
142 			     const u8 data_type, const u8 *data,
143 			     size_t data_len)
144 {
145 	struct nci_conn_info    *conn_info;
146 	struct sk_buff *skb;
147 	int len, i, r;
148 	u8 cb = pipe;
149 
150 	conn_info = ndev->hci_dev->conn_info;
151 	if (!conn_info)
152 		return -EPROTO;
153 
154 	i = 0;
155 	skb = nci_skb_alloc(ndev, conn_info->max_pkt_payload_len +
156 			    NCI_DATA_HDR_SIZE, GFP_KERNEL);
157 	if (!skb)
158 		return -ENOMEM;
159 
160 	skb_reserve(skb, NCI_DATA_HDR_SIZE + 2);
161 	*(u8 *)skb_push(skb, 1) = data_type;
162 
163 	do {
164 		len = conn_info->max_pkt_payload_len;
165 
166 		/* If last packet add NCI_HFP_NO_CHAINING */
167 		if (i + conn_info->max_pkt_payload_len -
168 		    (skb->len + 1) >= data_len) {
169 			cb |= NCI_HFP_NO_CHAINING;
170 			len = data_len - i;
171 		} else {
172 			len = conn_info->max_pkt_payload_len - skb->len - 1;
173 		}
174 
175 		*(u8 *)skb_push(skb, 1) = cb;
176 
177 		if (len > 0)
178 			skb_put_data(skb, data + i, len);
179 
180 		r = nci_send_data(ndev, conn_info->conn_id, skb);
181 		if (r < 0)
182 			return r;
183 
184 		i += len;
185 
186 		if (i < data_len) {
187 			skb = nci_skb_alloc(ndev,
188 					    conn_info->max_pkt_payload_len +
189 					    NCI_DATA_HDR_SIZE, GFP_KERNEL);
190 			if (!skb)
191 				return -ENOMEM;
192 
193 			skb_reserve(skb, NCI_DATA_HDR_SIZE + 1);
194 		}
195 	} while (i < data_len);
196 
197 	return i;
198 }
199 
200 static void nci_hci_send_data_req(struct nci_dev *ndev, unsigned long opt)
201 {
202 	struct nci_data *data = (struct nci_data *)opt;
203 
204 	nci_hci_send_data(ndev, data->pipe, data->cmd,
205 			  data->data, data->data_len);
206 }
207 
208 int nci_hci_send_event(struct nci_dev *ndev, u8 gate, u8 event,
209 		       const u8 *param, size_t param_len)
210 {
211 	u8 pipe = ndev->hci_dev->gate2pipe[gate];
212 
213 	if (pipe == NCI_HCI_INVALID_PIPE)
214 		return -EADDRNOTAVAIL;
215 
216 	return nci_hci_send_data(ndev, pipe,
217 			NCI_HCP_HEADER(NCI_HCI_HCP_EVENT, event),
218 			param, param_len);
219 }
220 EXPORT_SYMBOL(nci_hci_send_event);
221 
222 int nci_hci_send_cmd(struct nci_dev *ndev, u8 gate, u8 cmd,
223 		     const u8 *param, size_t param_len,
224 		     struct sk_buff **skb)
225 {
226 	struct nci_hcp_message *message;
227 	struct nci_conn_info   *conn_info;
228 	struct nci_data data;
229 	int r;
230 	u8 pipe = ndev->hci_dev->gate2pipe[gate];
231 
232 	if (pipe == NCI_HCI_INVALID_PIPE)
233 		return -EADDRNOTAVAIL;
234 
235 	conn_info = ndev->hci_dev->conn_info;
236 	if (!conn_info)
237 		return -EPROTO;
238 
239 	data.conn_id = conn_info->conn_id;
240 	data.pipe = pipe;
241 	data.cmd = NCI_HCP_HEADER(NCI_HCI_HCP_COMMAND, cmd);
242 	data.data = param;
243 	data.data_len = param_len;
244 
245 	r = nci_request(ndev, nci_hci_send_data_req, (unsigned long)&data,
246 			msecs_to_jiffies(NCI_DATA_TIMEOUT));
247 	if (r == NCI_STATUS_OK) {
248 		message = (struct nci_hcp_message *)conn_info->rx_skb->data;
249 		r = nci_hci_result_to_errno(
250 			NCI_HCP_MSG_GET_CMD(message->header));
251 		skb_pull(conn_info->rx_skb, NCI_HCI_HCP_MESSAGE_HEADER_LEN);
252 
253 		if (!r && skb)
254 			*skb = conn_info->rx_skb;
255 	}
256 
257 	return r;
258 }
259 EXPORT_SYMBOL(nci_hci_send_cmd);
260 
261 int nci_hci_clear_all_pipes(struct nci_dev *ndev)
262 {
263 	int r;
264 
265 	r = nci_hci_send_cmd(ndev, NCI_HCI_ADMIN_GATE,
266 			     NCI_HCI_ADM_CLEAR_ALL_PIPE, NULL, 0, NULL);
267 	if (r < 0)
268 		return r;
269 
270 	nci_hci_reset_pipes(ndev->hci_dev);
271 	return r;
272 }
273 EXPORT_SYMBOL(nci_hci_clear_all_pipes);
274 
275 static void nci_hci_event_received(struct nci_dev *ndev, u8 pipe,
276 				   u8 event, struct sk_buff *skb)
277 {
278 	if (ndev->ops->hci_event_received)
279 		ndev->ops->hci_event_received(ndev, pipe, event, skb);
280 }
281 
282 static void nci_hci_cmd_received(struct nci_dev *ndev, u8 pipe,
283 				 u8 cmd, struct sk_buff *skb)
284 {
285 	u8 gate = ndev->hci_dev->pipes[pipe].gate;
286 	u8 status = NCI_HCI_ANY_OK | ~NCI_HCI_FRAGMENT;
287 	u8 dest_gate, new_pipe;
288 	struct nci_hci_create_pipe_resp *create_info;
289 	struct nci_hci_delete_pipe_noti *delete_info;
290 	struct nci_hci_all_pipe_cleared_noti *cleared_info;
291 
292 	pr_debug("from gate %x pipe %x cmd %x\n", gate, pipe, cmd);
293 
294 	switch (cmd) {
295 	case NCI_HCI_ADM_NOTIFY_PIPE_CREATED:
296 		if (skb->len != 5) {
297 			status = NCI_HCI_ANY_E_NOK;
298 			goto exit;
299 		}
300 		create_info = (struct nci_hci_create_pipe_resp *)skb->data;
301 		dest_gate = create_info->dest_gate;
302 		new_pipe = create_info->pipe;
303 		if (new_pipe >= NCI_HCI_MAX_PIPES) {
304 			status = NCI_HCI_ANY_E_NOK;
305 			goto exit;
306 		}
307 
308 		/* Save the new created pipe and bind with local gate,
309 		 * the description for skb->data[3] is destination gate id
310 		 * but since we received this cmd from host controller, we
311 		 * are the destination and it is our local gate
312 		 */
313 		ndev->hci_dev->gate2pipe[dest_gate] = new_pipe;
314 		ndev->hci_dev->pipes[new_pipe].gate = dest_gate;
315 		ndev->hci_dev->pipes[new_pipe].host =
316 						create_info->src_host;
317 		break;
318 	case NCI_HCI_ANY_OPEN_PIPE:
319 		/* If the pipe is not created report an error */
320 		if (gate == NCI_HCI_INVALID_GATE) {
321 			status = NCI_HCI_ANY_E_NOK;
322 			goto exit;
323 		}
324 		break;
325 	case NCI_HCI_ADM_NOTIFY_PIPE_DELETED:
326 		if (skb->len != 1) {
327 			status = NCI_HCI_ANY_E_NOK;
328 			goto exit;
329 		}
330 		delete_info = (struct nci_hci_delete_pipe_noti *)skb->data;
331 		if (delete_info->pipe >= NCI_HCI_MAX_PIPES) {
332 			status = NCI_HCI_ANY_E_NOK;
333 			goto exit;
334 		}
335 
336 		ndev->hci_dev->pipes[delete_info->pipe].gate =
337 						NCI_HCI_INVALID_GATE;
338 		ndev->hci_dev->pipes[delete_info->pipe].host =
339 						NCI_HCI_INVALID_HOST;
340 		break;
341 	case NCI_HCI_ADM_NOTIFY_ALL_PIPE_CLEARED:
342 		if (skb->len != 1) {
343 			status = NCI_HCI_ANY_E_NOK;
344 			goto exit;
345 		}
346 
347 		cleared_info =
348 			(struct nci_hci_all_pipe_cleared_noti *)skb->data;
349 		nci_hci_reset_pipes_per_host(ndev, cleared_info->host);
350 		break;
351 	default:
352 		pr_debug("Discarded unknown cmd %x to gate %x\n", cmd, gate);
353 		break;
354 	}
355 
356 	if (ndev->ops->hci_cmd_received)
357 		ndev->ops->hci_cmd_received(ndev, pipe, cmd, skb);
358 
359 exit:
360 	nci_hci_send_data(ndev, pipe, status, NULL, 0);
361 
362 	kfree_skb(skb);
363 }
364 
365 static void nci_hci_resp_received(struct nci_dev *ndev, u8 pipe,
366 				  u8 result, struct sk_buff *skb)
367 {
368 	struct nci_conn_info    *conn_info;
369 	u8 status = result;
370 
371 	conn_info = ndev->hci_dev->conn_info;
372 	if (!conn_info) {
373 		status = NCI_STATUS_REJECTED;
374 		goto exit;
375 	}
376 
377 	conn_info->rx_skb = skb;
378 
379 exit:
380 	nci_req_complete(ndev, NCI_STATUS_OK);
381 }
382 
383 /* Receive hcp message for pipe, with type and cmd.
384  * skb contains optional message data only.
385  */
386 static void nci_hci_hcp_message_rx(struct nci_dev *ndev, u8 pipe,
387 				   u8 type, u8 instruction, struct sk_buff *skb)
388 {
389 	switch (type) {
390 	case NCI_HCI_HCP_RESPONSE:
391 		nci_hci_resp_received(ndev, pipe, instruction, skb);
392 		break;
393 	case NCI_HCI_HCP_COMMAND:
394 		nci_hci_cmd_received(ndev, pipe, instruction, skb);
395 		break;
396 	case NCI_HCI_HCP_EVENT:
397 		nci_hci_event_received(ndev, pipe, instruction, skb);
398 		break;
399 	default:
400 		pr_err("UNKNOWN MSG Type %d, instruction=%d\n",
401 		       type, instruction);
402 		kfree_skb(skb);
403 		break;
404 	}
405 
406 	nci_req_complete(ndev, NCI_STATUS_OK);
407 }
408 
409 static void nci_hci_msg_rx_work(struct work_struct *work)
410 {
411 	struct nci_hci_dev *hdev =
412 		container_of(work, struct nci_hci_dev, msg_rx_work);
413 	struct sk_buff *skb;
414 	struct nci_hcp_message *message;
415 	u8 pipe, type, instruction;
416 
417 	while ((skb = skb_dequeue(&hdev->msg_rx_queue)) != NULL) {
418 		pipe = NCI_HCP_MSG_GET_PIPE(skb->data[0]);
419 		skb_pull(skb, NCI_HCI_HCP_PACKET_HEADER_LEN);
420 		message = (struct nci_hcp_message *)skb->data;
421 		type = NCI_HCP_MSG_GET_TYPE(message->header);
422 		instruction = NCI_HCP_MSG_GET_CMD(message->header);
423 		skb_pull(skb, NCI_HCI_HCP_MESSAGE_HEADER_LEN);
424 
425 		nci_hci_hcp_message_rx(hdev->ndev, pipe,
426 				       type, instruction, skb);
427 	}
428 }
429 
430 void nci_hci_data_received_cb(void *context,
431 			      struct sk_buff *skb, int err)
432 {
433 	struct nci_dev *ndev = (struct nci_dev *)context;
434 	struct nci_hcp_packet *packet;
435 	u8 pipe, type;
436 	struct sk_buff *hcp_skb;
437 	struct sk_buff *frag_skb;
438 	int msg_len;
439 
440 	pr_debug("\n");
441 
442 	if (err) {
443 		nci_req_complete(ndev, err);
444 		return;
445 	}
446 
447 	packet = (struct nci_hcp_packet *)skb->data;
448 	if ((packet->header & ~NCI_HCI_FRAGMENT) == 0) {
449 		skb_queue_tail(&ndev->hci_dev->rx_hcp_frags, skb);
450 		return;
451 	}
452 
453 	/* it's the last fragment. Does it need re-aggregation? */
454 	if (skb_queue_len(&ndev->hci_dev->rx_hcp_frags)) {
455 		pipe = NCI_HCP_MSG_GET_PIPE(packet->header);
456 		skb_queue_tail(&ndev->hci_dev->rx_hcp_frags, skb);
457 
458 		msg_len = 0;
459 		skb_queue_walk(&ndev->hci_dev->rx_hcp_frags, frag_skb) {
460 			msg_len += (frag_skb->len -
461 				    NCI_HCI_HCP_PACKET_HEADER_LEN);
462 		}
463 
464 		hcp_skb = nfc_alloc_recv_skb(NCI_HCI_HCP_PACKET_HEADER_LEN +
465 					     msg_len, GFP_KERNEL);
466 		if (!hcp_skb) {
467 			nci_req_complete(ndev, -ENOMEM);
468 			return;
469 		}
470 
471 		skb_put_u8(hcp_skb, pipe);
472 
473 		skb_queue_walk(&ndev->hci_dev->rx_hcp_frags, frag_skb) {
474 			msg_len = frag_skb->len - NCI_HCI_HCP_PACKET_HEADER_LEN;
475 			skb_put_data(hcp_skb,
476 				     frag_skb->data + NCI_HCI_HCP_PACKET_HEADER_LEN,
477 				     msg_len);
478 		}
479 
480 		skb_queue_purge(&ndev->hci_dev->rx_hcp_frags);
481 	} else {
482 		packet->header &= NCI_HCI_FRAGMENT;
483 		hcp_skb = skb;
484 	}
485 
486 	/* if this is a response, dispatch immediately to
487 	 * unblock waiting cmd context. Otherwise, enqueue to dispatch
488 	 * in separate context where handler can also execute command.
489 	 */
490 	packet = (struct nci_hcp_packet *)hcp_skb->data;
491 	type = NCI_HCP_MSG_GET_TYPE(packet->message.header);
492 	if (type == NCI_HCI_HCP_RESPONSE) {
493 		pipe = NCI_HCP_MSG_GET_PIPE(packet->header);
494 		skb_pull(hcp_skb, NCI_HCI_HCP_PACKET_HEADER_LEN);
495 		nci_hci_hcp_message_rx(ndev, pipe, type,
496 				       NCI_STATUS_OK, hcp_skb);
497 	} else {
498 		skb_queue_tail(&ndev->hci_dev->msg_rx_queue, hcp_skb);
499 		schedule_work(&ndev->hci_dev->msg_rx_work);
500 	}
501 }
502 
503 int nci_hci_open_pipe(struct nci_dev *ndev, u8 pipe)
504 {
505 	struct nci_data data;
506 	struct nci_conn_info    *conn_info;
507 
508 	conn_info = ndev->hci_dev->conn_info;
509 	if (!conn_info)
510 		return -EPROTO;
511 
512 	data.conn_id = conn_info->conn_id;
513 	data.pipe = pipe;
514 	data.cmd = NCI_HCP_HEADER(NCI_HCI_HCP_COMMAND,
515 				       NCI_HCI_ANY_OPEN_PIPE);
516 	data.data = NULL;
517 	data.data_len = 0;
518 
519 	return nci_request(ndev, nci_hci_send_data_req,
520 			(unsigned long)&data,
521 			msecs_to_jiffies(NCI_DATA_TIMEOUT));
522 }
523 EXPORT_SYMBOL(nci_hci_open_pipe);
524 
525 static u8 nci_hci_create_pipe(struct nci_dev *ndev, u8 dest_host,
526 			      u8 dest_gate, int *result)
527 {
528 	u8 pipe;
529 	struct sk_buff *skb;
530 	struct nci_hci_create_pipe_params params;
531 	struct nci_hci_create_pipe_resp *resp;
532 
533 	pr_debug("gate=%d\n", dest_gate);
534 
535 	params.src_gate = NCI_HCI_ADMIN_GATE;
536 	params.dest_host = dest_host;
537 	params.dest_gate = dest_gate;
538 
539 	*result = nci_hci_send_cmd(ndev, NCI_HCI_ADMIN_GATE,
540 				   NCI_HCI_ADM_CREATE_PIPE,
541 				   (u8 *)&params, sizeof(params), &skb);
542 	if (*result < 0)
543 		return NCI_HCI_INVALID_PIPE;
544 
545 	resp = (struct nci_hci_create_pipe_resp *)skb->data;
546 	pipe = resp->pipe;
547 	kfree_skb(skb);
548 
549 	pr_debug("pipe created=%d\n", pipe);
550 
551 	return pipe;
552 }
553 
554 static int nci_hci_delete_pipe(struct nci_dev *ndev, u8 pipe)
555 {
556 	pr_debug("\n");
557 
558 	return nci_hci_send_cmd(ndev, NCI_HCI_ADMIN_GATE,
559 				NCI_HCI_ADM_DELETE_PIPE, &pipe, 1, NULL);
560 }
561 
562 int nci_hci_set_param(struct nci_dev *ndev, u8 gate, u8 idx,
563 		      const u8 *param, size_t param_len)
564 {
565 	struct nci_hcp_message *message;
566 	struct nci_conn_info *conn_info;
567 	struct nci_data data;
568 	int r;
569 	u8 *tmp;
570 	u8 pipe = ndev->hci_dev->gate2pipe[gate];
571 
572 	pr_debug("idx=%d to gate %d\n", idx, gate);
573 
574 	if (pipe == NCI_HCI_INVALID_PIPE)
575 		return -EADDRNOTAVAIL;
576 
577 	conn_info = ndev->hci_dev->conn_info;
578 	if (!conn_info)
579 		return -EPROTO;
580 
581 	tmp = kmalloc(1 + param_len, GFP_KERNEL);
582 	if (!tmp)
583 		return -ENOMEM;
584 
585 	*tmp = idx;
586 	memcpy(tmp + 1, param, param_len);
587 
588 	data.conn_id = conn_info->conn_id;
589 	data.pipe = pipe;
590 	data.cmd = NCI_HCP_HEADER(NCI_HCI_HCP_COMMAND,
591 				       NCI_HCI_ANY_SET_PARAMETER);
592 	data.data = tmp;
593 	data.data_len = param_len + 1;
594 
595 	r = nci_request(ndev, nci_hci_send_data_req,
596 			(unsigned long)&data,
597 			msecs_to_jiffies(NCI_DATA_TIMEOUT));
598 	if (r == NCI_STATUS_OK) {
599 		message = (struct nci_hcp_message *)conn_info->rx_skb->data;
600 		r = nci_hci_result_to_errno(
601 			NCI_HCP_MSG_GET_CMD(message->header));
602 		skb_pull(conn_info->rx_skb, NCI_HCI_HCP_MESSAGE_HEADER_LEN);
603 	}
604 
605 	kfree(tmp);
606 	return r;
607 }
608 EXPORT_SYMBOL(nci_hci_set_param);
609 
610 int nci_hci_get_param(struct nci_dev *ndev, u8 gate, u8 idx,
611 		      struct sk_buff **skb)
612 {
613 	struct nci_hcp_message *message;
614 	struct nci_conn_info    *conn_info;
615 	struct nci_data data;
616 	int r;
617 	u8 pipe = ndev->hci_dev->gate2pipe[gate];
618 
619 	pr_debug("idx=%d to gate %d\n", idx, gate);
620 
621 	if (pipe == NCI_HCI_INVALID_PIPE)
622 		return -EADDRNOTAVAIL;
623 
624 	conn_info = ndev->hci_dev->conn_info;
625 	if (!conn_info)
626 		return -EPROTO;
627 
628 	data.conn_id = conn_info->conn_id;
629 	data.pipe = pipe;
630 	data.cmd = NCI_HCP_HEADER(NCI_HCI_HCP_COMMAND,
631 				  NCI_HCI_ANY_GET_PARAMETER);
632 	data.data = &idx;
633 	data.data_len = 1;
634 
635 	r = nci_request(ndev, nci_hci_send_data_req, (unsigned long)&data,
636 			msecs_to_jiffies(NCI_DATA_TIMEOUT));
637 
638 	if (r == NCI_STATUS_OK) {
639 		message = (struct nci_hcp_message *)conn_info->rx_skb->data;
640 		r = nci_hci_result_to_errno(
641 			NCI_HCP_MSG_GET_CMD(message->header));
642 		skb_pull(conn_info->rx_skb, NCI_HCI_HCP_MESSAGE_HEADER_LEN);
643 
644 		if (!r && skb)
645 			*skb = conn_info->rx_skb;
646 	}
647 
648 	return r;
649 }
650 EXPORT_SYMBOL(nci_hci_get_param);
651 
652 int nci_hci_connect_gate(struct nci_dev *ndev,
653 			 u8 dest_host, u8 dest_gate, u8 pipe)
654 {
655 	bool pipe_created = false;
656 	int r;
657 
658 	if (pipe == NCI_HCI_DO_NOT_OPEN_PIPE)
659 		return 0;
660 
661 	if (ndev->hci_dev->gate2pipe[dest_gate] != NCI_HCI_INVALID_PIPE)
662 		return -EADDRINUSE;
663 
664 	if (pipe != NCI_HCI_INVALID_PIPE)
665 		goto open_pipe;
666 
667 	switch (dest_gate) {
668 	case NCI_HCI_LINK_MGMT_GATE:
669 		pipe = NCI_HCI_LINK_MGMT_PIPE;
670 	break;
671 	case NCI_HCI_ADMIN_GATE:
672 		pipe = NCI_HCI_ADMIN_PIPE;
673 	break;
674 	default:
675 		pipe = nci_hci_create_pipe(ndev, dest_host, dest_gate, &r);
676 		if (pipe == NCI_HCI_INVALID_PIPE)
677 			return r;
678 		pipe_created = true;
679 		break;
680 	}
681 
682 open_pipe:
683 	r = nci_hci_open_pipe(ndev, pipe);
684 	if (r < 0) {
685 		if (pipe_created) {
686 			if (nci_hci_delete_pipe(ndev, pipe) < 0) {
687 				/* TODO: Cannot clean by deleting pipe...
688 				 * -> inconsistent state
689 				 */
690 			}
691 		}
692 		return r;
693 	}
694 
695 	ndev->hci_dev->pipes[pipe].gate = dest_gate;
696 	ndev->hci_dev->pipes[pipe].host = dest_host;
697 	ndev->hci_dev->gate2pipe[dest_gate] = pipe;
698 
699 	return 0;
700 }
701 EXPORT_SYMBOL(nci_hci_connect_gate);
702 
703 static int nci_hci_dev_connect_gates(struct nci_dev *ndev,
704 				     u8 gate_count,
705 				     struct nci_hci_gate *gates)
706 {
707 	int r;
708 
709 	while (gate_count--) {
710 		r = nci_hci_connect_gate(ndev, gates->dest_host,
711 					 gates->gate, gates->pipe);
712 		if (r < 0)
713 			return r;
714 		gates++;
715 	}
716 
717 	return 0;
718 }
719 
720 int nci_hci_dev_session_init(struct nci_dev *ndev)
721 {
722 	struct nci_conn_info    *conn_info;
723 	struct sk_buff *skb;
724 	int r;
725 
726 	ndev->hci_dev->count_pipes = 0;
727 	ndev->hci_dev->expected_pipes = 0;
728 
729 	conn_info = ndev->hci_dev->conn_info;
730 	if (!conn_info)
731 		return -EPROTO;
732 
733 	conn_info->data_exchange_cb = nci_hci_data_received_cb;
734 	conn_info->data_exchange_cb_context = ndev;
735 
736 	nci_hci_reset_pipes(ndev->hci_dev);
737 
738 	if (ndev->hci_dev->init_data.gates[0].gate != NCI_HCI_ADMIN_GATE)
739 		return -EPROTO;
740 
741 	r = nci_hci_connect_gate(ndev,
742 				 ndev->hci_dev->init_data.gates[0].dest_host,
743 				 ndev->hci_dev->init_data.gates[0].gate,
744 				 ndev->hci_dev->init_data.gates[0].pipe);
745 	if (r < 0)
746 		return r;
747 
748 	r = nci_hci_get_param(ndev, NCI_HCI_ADMIN_GATE,
749 			      NCI_HCI_ADMIN_PARAM_SESSION_IDENTITY, &skb);
750 	if (r < 0)
751 		return r;
752 
753 	if (skb->len &&
754 	    skb->len == strlen(ndev->hci_dev->init_data.session_id) &&
755 	    !memcmp(ndev->hci_dev->init_data.session_id, skb->data, skb->len) &&
756 	    ndev->ops->hci_load_session) {
757 		/* Restore gate<->pipe table from some proprietary location. */
758 		r = ndev->ops->hci_load_session(ndev);
759 	} else {
760 		r = nci_hci_clear_all_pipes(ndev);
761 		if (r < 0)
762 			goto exit;
763 
764 		r = nci_hci_dev_connect_gates(ndev,
765 					      ndev->hci_dev->init_data.gate_count,
766 					      ndev->hci_dev->init_data.gates);
767 		if (r < 0)
768 			goto exit;
769 
770 		r = nci_hci_set_param(ndev, NCI_HCI_ADMIN_GATE,
771 				      NCI_HCI_ADMIN_PARAM_SESSION_IDENTITY,
772 				      ndev->hci_dev->init_data.session_id,
773 				      strlen(ndev->hci_dev->init_data.session_id));
774 	}
775 
776 exit:
777 	kfree_skb(skb);
778 
779 	return r;
780 }
781 EXPORT_SYMBOL(nci_hci_dev_session_init);
782 
783 struct nci_hci_dev *nci_hci_allocate(struct nci_dev *ndev)
784 {
785 	struct nci_hci_dev *hdev;
786 
787 	hdev = kzalloc(sizeof(*hdev), GFP_KERNEL);
788 	if (!hdev)
789 		return NULL;
790 
791 	skb_queue_head_init(&hdev->rx_hcp_frags);
792 	INIT_WORK(&hdev->msg_rx_work, nci_hci_msg_rx_work);
793 	skb_queue_head_init(&hdev->msg_rx_queue);
794 	hdev->ndev = ndev;
795 
796 	return hdev;
797 }
798