xref: /linux/net/nfc/hci/llc.c (revision 93df8a1ed6231727c5db94a80b1a6bd5ee67cec3)
1 /*
2  * Link Layer Control manager
3  *
4  * Copyright (C) 2012  Intel Corporation. All rights reserved.
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms and conditions of the GNU General Public License,
8  * version 2, as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, see <http://www.gnu.org/licenses/>.
17  */
18 
19 #include <net/nfc/llc.h>
20 
21 #include "llc.h"
22 
23 static LIST_HEAD(llc_engines);
24 
25 int nfc_llc_init(void)
26 {
27 	int r;
28 
29 	r = nfc_llc_nop_register();
30 	if (r)
31 		goto exit;
32 
33 	r = nfc_llc_shdlc_register();
34 	if (r)
35 		goto exit;
36 
37 	return 0;
38 
39 exit:
40 	nfc_llc_exit();
41 	return r;
42 }
43 
44 void nfc_llc_exit(void)
45 {
46 	struct nfc_llc_engine *llc_engine, *n;
47 
48 	list_for_each_entry_safe(llc_engine, n, &llc_engines, entry) {
49 		list_del(&llc_engine->entry);
50 		kfree(llc_engine->name);
51 		kfree(llc_engine);
52 	}
53 }
54 
55 int nfc_llc_register(const char *name, struct nfc_llc_ops *ops)
56 {
57 	struct nfc_llc_engine *llc_engine;
58 
59 	llc_engine = kzalloc(sizeof(struct nfc_llc_engine), GFP_KERNEL);
60 	if (llc_engine == NULL)
61 		return -ENOMEM;
62 
63 	llc_engine->name = kstrdup(name, GFP_KERNEL);
64 	if (llc_engine->name == NULL) {
65 		kfree(llc_engine);
66 		return -ENOMEM;
67 	}
68 	llc_engine->ops = ops;
69 
70 	INIT_LIST_HEAD(&llc_engine->entry);
71 	list_add_tail(&llc_engine->entry, &llc_engines);
72 
73 	return 0;
74 }
75 
76 static struct nfc_llc_engine *nfc_llc_name_to_engine(const char *name)
77 {
78 	struct nfc_llc_engine *llc_engine;
79 
80 	list_for_each_entry(llc_engine, &llc_engines, entry) {
81 		if (strcmp(llc_engine->name, name) == 0)
82 			return llc_engine;
83 	}
84 
85 	return NULL;
86 }
87 
88 void nfc_llc_unregister(const char *name)
89 {
90 	struct nfc_llc_engine *llc_engine;
91 
92 	llc_engine = nfc_llc_name_to_engine(name);
93 	if (llc_engine == NULL)
94 		return;
95 
96 	list_del(&llc_engine->entry);
97 	kfree(llc_engine->name);
98 	kfree(llc_engine);
99 }
100 
101 struct nfc_llc *nfc_llc_allocate(const char *name, struct nfc_hci_dev *hdev,
102 				 xmit_to_drv_t xmit_to_drv,
103 				 rcv_to_hci_t rcv_to_hci, int tx_headroom,
104 				 int tx_tailroom, llc_failure_t llc_failure)
105 {
106 	struct nfc_llc_engine *llc_engine;
107 	struct nfc_llc *llc;
108 
109 	llc_engine = nfc_llc_name_to_engine(name);
110 	if (llc_engine == NULL)
111 		return NULL;
112 
113 	llc = kzalloc(sizeof(struct nfc_llc), GFP_KERNEL);
114 	if (llc == NULL)
115 		return NULL;
116 
117 	llc->data = llc_engine->ops->init(hdev, xmit_to_drv, rcv_to_hci,
118 					  tx_headroom, tx_tailroom,
119 					  &llc->rx_headroom, &llc->rx_tailroom,
120 					  llc_failure);
121 	if (llc->data == NULL) {
122 		kfree(llc);
123 		return NULL;
124 	}
125 	llc->ops = llc_engine->ops;
126 
127 	return llc;
128 }
129 
130 void nfc_llc_free(struct nfc_llc *llc)
131 {
132 	llc->ops->deinit(llc);
133 	kfree(llc);
134 }
135 
136 inline void nfc_llc_get_rx_head_tail_room(struct nfc_llc *llc, int *rx_headroom,
137 					  int *rx_tailroom)
138 {
139 	*rx_headroom = llc->rx_headroom;
140 	*rx_tailroom = llc->rx_tailroom;
141 }
142 
143 inline int nfc_llc_start(struct nfc_llc *llc)
144 {
145 	return llc->ops->start(llc);
146 }
147 
148 inline int nfc_llc_stop(struct nfc_llc *llc)
149 {
150 	return llc->ops->stop(llc);
151 }
152 
153 inline void nfc_llc_rcv_from_drv(struct nfc_llc *llc, struct sk_buff *skb)
154 {
155 	llc->ops->rcv_from_drv(llc, skb);
156 }
157 
158 inline int nfc_llc_xmit_from_hci(struct nfc_llc *llc, struct sk_buff *skb)
159 {
160 	return llc->ops->xmit_from_hci(llc, skb);
161 }
162 
163 inline void *nfc_llc_get_data(struct nfc_llc *llc)
164 {
165 	return llc->data;
166 }
167