xref: /openbmc/linux/net/nfc/hci/llc.c (revision 37be287c)
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 struct list_head llc_engines;
24 
25 int nfc_llc_init(void)
26 {
27 	int r;
28 
29 	INIT_LIST_HEAD(&llc_engines);
30 
31 	r = nfc_llc_nop_register();
32 	if (r)
33 		goto exit;
34 
35 	r = nfc_llc_shdlc_register();
36 	if (r)
37 		goto exit;
38 
39 	return 0;
40 
41 exit:
42 	nfc_llc_exit();
43 	return r;
44 }
45 
46 void nfc_llc_exit(void)
47 {
48 	struct nfc_llc_engine *llc_engine, *n;
49 
50 	list_for_each_entry_safe(llc_engine, n, &llc_engines, entry) {
51 		list_del(&llc_engine->entry);
52 		kfree(llc_engine->name);
53 		kfree(llc_engine);
54 	}
55 }
56 
57 int nfc_llc_register(const char *name, struct nfc_llc_ops *ops)
58 {
59 	struct nfc_llc_engine *llc_engine;
60 
61 	llc_engine = kzalloc(sizeof(struct nfc_llc_engine), GFP_KERNEL);
62 	if (llc_engine == NULL)
63 		return -ENOMEM;
64 
65 	llc_engine->name = kstrdup(name, GFP_KERNEL);
66 	if (llc_engine->name == NULL) {
67 		kfree(llc_engine);
68 		return -ENOMEM;
69 	}
70 	llc_engine->ops = ops;
71 
72 	INIT_LIST_HEAD(&llc_engine->entry);
73 	list_add_tail(&llc_engine->entry, &llc_engines);
74 
75 	return 0;
76 }
77 
78 static struct nfc_llc_engine *nfc_llc_name_to_engine(const char *name)
79 {
80 	struct nfc_llc_engine *llc_engine;
81 
82 	list_for_each_entry(llc_engine, &llc_engines, entry) {
83 		if (strcmp(llc_engine->name, name) == 0)
84 			return llc_engine;
85 	}
86 
87 	return NULL;
88 }
89 
90 void nfc_llc_unregister(const char *name)
91 {
92 	struct nfc_llc_engine *llc_engine;
93 
94 	llc_engine = nfc_llc_name_to_engine(name);
95 	if (llc_engine == NULL)
96 		return;
97 
98 	list_del(&llc_engine->entry);
99 	kfree(llc_engine->name);
100 	kfree(llc_engine);
101 }
102 
103 struct nfc_llc *nfc_llc_allocate(const char *name, struct nfc_hci_dev *hdev,
104 				 xmit_to_drv_t xmit_to_drv,
105 				 rcv_to_hci_t rcv_to_hci, int tx_headroom,
106 				 int tx_tailroom, llc_failure_t llc_failure)
107 {
108 	struct nfc_llc_engine *llc_engine;
109 	struct nfc_llc *llc;
110 
111 	llc_engine = nfc_llc_name_to_engine(name);
112 	if (llc_engine == NULL)
113 		return NULL;
114 
115 	llc = kzalloc(sizeof(struct nfc_llc), GFP_KERNEL);
116 	if (llc == NULL)
117 		return NULL;
118 
119 	llc->data = llc_engine->ops->init(hdev, xmit_to_drv, rcv_to_hci,
120 					  tx_headroom, tx_tailroom,
121 					  &llc->rx_headroom, &llc->rx_tailroom,
122 					  llc_failure);
123 	if (llc->data == NULL) {
124 		kfree(llc);
125 		return NULL;
126 	}
127 	llc->ops = llc_engine->ops;
128 
129 	return llc;
130 }
131 
132 void nfc_llc_free(struct nfc_llc *llc)
133 {
134 	llc->ops->deinit(llc);
135 	kfree(llc);
136 }
137 
138 inline void nfc_llc_get_rx_head_tail_room(struct nfc_llc *llc, int *rx_headroom,
139 					  int *rx_tailroom)
140 {
141 	*rx_headroom = llc->rx_headroom;
142 	*rx_tailroom = llc->rx_tailroom;
143 }
144 
145 inline int nfc_llc_start(struct nfc_llc *llc)
146 {
147 	return llc->ops->start(llc);
148 }
149 
150 inline int nfc_llc_stop(struct nfc_llc *llc)
151 {
152 	return llc->ops->stop(llc);
153 }
154 
155 inline void nfc_llc_rcv_from_drv(struct nfc_llc *llc, struct sk_buff *skb)
156 {
157 	llc->ops->rcv_from_drv(llc, skb);
158 }
159 
160 inline int nfc_llc_xmit_from_hci(struct nfc_llc *llc, struct sk_buff *skb)
161 {
162 	return llc->ops->xmit_from_hci(llc, skb);
163 }
164 
165 inline void *nfc_llc_get_data(struct nfc_llc *llc)
166 {
167 	return llc->data;
168 }
169