summaryrefslogtreecommitdiff
path: root/net/nfc/hci/command.c
blob: af6bacb3ba9866b1de62afcde3b8c3cf9bfe524a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (C) 2012  Intel Corporation. All rights reserved.
 */

#define pr_fmt(fmt) "hci: %s: " fmt, __func__

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/module.h>

#include <net/nfc/hci.h>

#include "hci.h"

#define MAX_FWI 4949

static int nfc_hci_execute_cmd_async(struct nfc_hci_dev *hdev, u8 pipe, u8 cmd,
			       const u8 *param, size_t param_len,
			       data_exchange_cb_t cb, void *cb_context)
{
	pr_debug("exec cmd async through pipe=%d, cmd=%d, plen=%zd\n", pipe,
		 cmd, param_len);

	/* TODO: Define hci cmd execution delay. Should it be the same
	 * for all commands?
	 */
	return nfc_hci_hcp_message_tx(hdev, pipe, NFC_HCI_HCP_COMMAND, cmd,
				      param, param_len, cb, cb_context, MAX_FWI);
}

/*
 * HCI command execution completion callback.
 * err will be a standard linux error (may be converted from HCI response)
 * skb contains the response data and must be disposed, or may be NULL if
 * an error occurred
 */
static void nfc_hci_execute_cb(void *context, struct sk_buff *skb, int err)
{
	struct hcp_exec_waiter *hcp_ew = (struct hcp_exec_waiter *)context;

	pr_debug("HCI Cmd completed with result=%d\n", err);

	hcp_ew->exec_result = err;
	if (hcp_ew->exec_result == 0)
		hcp_ew->result_skb = skb;
	else
		kfree_skb(skb);
	hcp_ew->exec_complete = true;

	wake_up(hcp_ew->wq);
}

static int nfc_hci_execute_cmd(struct nfc_hci_dev *hdev, u8 pipe, u8 cmd,
			       const u8 *param, size_t param_len,
			       struct sk_buff **skb)
{
	DECLARE_WAIT_QUEUE_HEAD_ONSTACK(ew_wq);
	struct hcp_exec_waiter hcp_ew;
	hcp_ew.wq = &ew_wq;
	hcp_ew.exec_complete = false;
	hcp_ew.result_skb = NULL;

	pr_debug("exec cmd sync through pipe=%d, cmd=%d, plen=%zd\n", pipe,
		 cmd, param_len);

	/* TODO: Define hci cmd execution delay. Should it be the same
	 * for all commands?
	 */
	hcp_ew.exec_result = nfc_hci_hcp_message_tx(hdev, pipe,
						    NFC_HCI_HCP_COMMAND, cmd,
						    param, param_len,
						    nfc_hci_execute_cb, &hcp_ew,
						    MAX_FWI);
	if (hcp_ew.exec_result < 0)
		return hcp_ew.exec_result;

	wait_event(ew_wq, hcp_ew.exec_complete == true);

	if (hcp_ew.exec_result == 0) {
		if (skb)
			*skb = hcp_ew.result_skb;
		else
			kfree_skb(hcp_ew.result_skb);
	}

	return hcp_ew.exec_result;
}

int nfc_hci_send_event(struct nfc_hci_dev *hdev, u8 gate, u8 event,
		       const u8 *param, size_t param_len)
{
	u8 pipe;

	pr_debug("%d to gate %d\n", event, gate);

	pipe = hdev->gate2pipe[gate];
	if (pipe == NFC_HCI_INVALID_PIPE)
		return -EADDRNOTAVAIL;

	return nfc_hci_hcp_message_tx(hdev, pipe, NFC_HCI_HCP_EVENT, event,
				      param, param_len, NULL, NULL, 0);
}
EXPORT_SYMBOL(nfc_hci_send_event);

/*
 * Execute an hci command sent to gate.
 * skb will contain response data if success. skb can be NULL if you are not
 * interested by the response.
 */
int nfc_hci_send_cmd(struct nfc_hci_dev *hdev, u8 gate, u8 cmd,
		     const u8 *param, size_t param_len, struct sk_buff **skb)
{
	u8 pipe;

	pipe = hdev->gate2pipe[gate];
	if (pipe == NFC_HCI_INVALID_PIPE)
		return -EADDRNOTAVAIL;

	return nfc_hci_execute_cmd(hdev, pipe, cmd, param, param_len, skb);
}
EXPORT_SYMBOL(nfc_hci_send_cmd);

int nfc_hci_send_cmd_async(struct nfc_hci_dev *hdev, u8 gate, u8 cmd,
			   const u8 *param, size_t param_len,
			   data_exchange_cb_t cb, void *cb_context)
{
	u8 pipe;

	pipe = hdev->gate2pipe[gate];
	if (pipe == NFC_HCI_INVALID_PIPE)
		return -EADDRNOTAVAIL;

	return nfc_hci_execute_cmd_async(hdev, pipe, cmd, param, param_len,
					 cb, cb_context);
}
EXPORT_SYMBOL(nfc_hci_send_cmd_async);

int nfc_hci_set_param(struct nfc_hci_dev *hdev, u8 gate, u8 idx,
		      const u8 *param, size_t param_len)
{
	int r;
	u8 *tmp;

	/* TODO ELa: reg idx must be inserted before param, but we don't want
	 * to ask the caller to do it to keep a simpler API.
	 * For now, just create a new temporary param buffer. This is far from
	 * optimal though, and the plan is to modify APIs to pass idx down to
	 * nfc_hci_hcp_message_tx where the frame is actually built, thereby
	 * eliminating the need for the temp allocation-copy here.
	 */

	pr_debug("idx=%d to gate %d\n", idx, gate);

	tmp = kmalloc(1 + param_len, GFP_KERNEL);
	if (tmp == NULL)
		return -ENOMEM;

	*tmp = idx;
	memcpy(tmp + 1, param, param_len);

	r = nfc_hci_send_cmd(hdev, gate, NFC_HCI_ANY_SET_PARAMETER,
			     tmp, param_len + 1, NULL);

	kfree(tmp);

	return r;
}
EXPORT_SYMBOL(nfc_hci_set_param);

int nfc_hci_get_param(struct nfc_hci_dev *hdev, u8 gate, u8 idx,
		      struct sk_buff **skb)
{
	pr_debug("gate=%d regidx=%d\n", gate, idx);

	return nfc_hci_send_cmd(hdev, gate, NFC_HCI_ANY_GET_PARAMETER,
				&idx, 1, skb);
}
EXPORT_SYMBOL(nfc_hci_get_param);

static int nfc_hci_open_pipe(struct nfc_hci_dev *hdev, u8 pipe)
{
	struct sk_buff *skb;
	int r;

	pr_debug("pipe=%d\n", pipe);

	r = nfc_hci_execute_cmd(hdev, pipe, NFC_HCI_ANY_OPEN_PIPE,
				NULL, 0, &skb);
	if (r == 0) {
		/* dest host other than host controller will send
		 * number of pipes already open on this gate before
		 * execution. The number can be found in skb->data[0]
		 */
		kfree_skb(skb);
	}

	return r;
}

static int nfc_hci_close_pipe(struct nfc_hci_dev *hdev, u8 pipe)
{
	return nfc_hci_execute_cmd(hdev, pipe, NFC_HCI_ANY_CLOSE_PIPE,
				   NULL, 0, NULL);
}

static u8 nfc_hci_create_pipe(struct nfc_hci_dev *hdev, u8 dest_host,
			      u8 dest_gate, int *result)
{
	struct sk_buff *skb;
	struct hci_create_pipe_params params;
	struct hci_create_pipe_resp *resp;
	u8 pipe;

	pr_debug("gate=%d\n", dest_gate);

	params.src_gate = NFC_HCI_ADMIN_GATE;
	params.dest_host = dest_host;
	params.dest_gate = dest_gate;

	*result = nfc_hci_execute_cmd(hdev, NFC_HCI_ADMIN_PIPE,
				      NFC_HCI_ADM_CREATE_PIPE,
				      (u8 *) &params, sizeof(params), &skb);
	if (*result < 0)
		return NFC_HCI_INVALID_PIPE;

	resp = (struct hci_create_pipe_resp *)skb->data;
	pipe = resp->pipe;
	kfree_skb(skb);

	pr_debug("pipe created=%d\n", pipe);

	return pipe;
}

static int nfc_hci_delete_pipe(struct nfc_hci_dev *hdev, u8 pipe)
{
	return nfc_hci_execute_cmd(hdev, NFC_HCI_ADMIN_PIPE,
				   NFC_HCI_ADM_DELETE_PIPE, &pipe, 1, NULL);
}

static int nfc_hci_clear_all_pipes(struct nfc_hci_dev *hdev)
{
	u8 param[2];
	size_t param_len = 2;

	/* TODO: Find out what the identity reference data is
	 * and fill param with it. HCI spec 6.1.3.5 */

	if (test_bit(NFC_HCI_QUIRK_SHORT_CLEAR, &hdev->quirks))
		param_len = 0;

	return nfc_hci_execute_cmd(hdev, NFC_HCI_ADMIN_PIPE,
				   NFC_HCI_ADM_CLEAR_ALL_PIPE, param, param_len,
				   NULL);
}

int nfc_hci_disconnect_gate(struct nfc_hci_dev *hdev, u8 gate)
{
	int r;
	u8 pipe = hdev->gate2pipe[gate];

	if (pipe == NFC_HCI_INVALID_PIPE)
		return -EADDRNOTAVAIL;

	r = nfc_hci_close_pipe(hdev, pipe);
	if (r < 0)
		return r;

	if (pipe != NFC_HCI_LINK_MGMT_PIPE && pipe != NFC_HCI_ADMIN_PIPE) {
		r = nfc_hci_delete_pipe(hdev, pipe);
		if (r < 0)
			return r;
	}

	hdev->gate2pipe[gate] = NFC_HCI_INVALID_PIPE;

	return 0;
}
EXPORT_SYMBOL(nfc_hci_disconnect_gate);

int nfc_hci_disconnect_all_gates(struct nfc_hci_dev *hdev)
{
	int r;

	r = nfc_hci_clear_all_pipes(hdev);
	if (r < 0)
		return r;

	nfc_hci_reset_pipes(hdev);

	return 0;
}
EXPORT_SYMBOL(nfc_hci_disconnect_all_gates);

int nfc_hci_connect_gate(struct nfc_hci_dev *hdev, u8 dest_host, u8 dest_gate,
			 u8 pipe)
{
	bool pipe_created = false;
	int r;

	if (pipe == NFC_HCI_DO_NOT_CREATE_PIPE)
		return 0;

	if (hdev->gate2pipe[dest_gate] != NFC_HCI_INVALID_PIPE)
		return -EADDRINUSE;

	if (pipe != NFC_HCI_INVALID_PIPE)
		goto open_pipe;

	switch (dest_gate) {
	case NFC_HCI_LINK_MGMT_GATE:
		pipe = NFC_HCI_LINK_MGMT_PIPE;
		break;
	case NFC_HCI_ADMIN_GATE:
		pipe = NFC_HCI_ADMIN_PIPE;
		break;
	default:
		pipe = nfc_hci_create_pipe(hdev, dest_host, dest_gate, &r);
		if (pipe == NFC_HCI_INVALID_PIPE)
			return r;
		pipe_created = true;
		break;
	}

open_pipe:
	r = nfc_hci_open_pipe(hdev, pipe);
	if (r < 0) {
		if (pipe_created)
			if (nfc_hci_delete_pipe(hdev, pipe) < 0) {
				/* TODO: Cannot clean by deleting pipe...
				 * -> inconsistent state */
			}
		return r;
	}

	hdev->pipes[pipe].gate = dest_gate;
	hdev->pipes[pipe].dest_host = dest_host;
	hdev->gate2pipe[dest_gate] = pipe;

	return 0;
}
EXPORT_SYMBOL(nfc_hci_connect_gate);