xref: /openbmc/linux/net/nfc/hci/llc.c (revision 2d6bed9c)
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, write to the
17  * Free Software Foundation, Inc.,
18  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19  */
20 
21 #include <net/nfc/llc.h>
22 
23 #include "llc.h"
24 
25 static struct list_head llc_engines;
26 
27 int nfc_llc_init(void)
28 {
29 	int r;
30 
31 	INIT_LIST_HEAD(&llc_engines);
32 
33 	r = nfc_llc_nop_register();
34 	if (r)
35 		goto exit;
36 
37 	r = nfc_llc_shdlc_register();
38 	if (r)
39 		goto exit;
40 
41 	return 0;
42 
43 exit:
44 	nfc_llc_exit();
45 	return r;
46 }
47 
48 void nfc_llc_exit(void)
49 {
50 	struct nfc_llc_engine *llc_engine, *n;
51 
52 	list_for_each_entry_safe(llc_engine, n, &llc_engines, entry) {
53 		list_del(&llc_engine->entry);
54 		kfree(llc_engine->name);
55 		kfree(llc_engine);
56 	}
57 }
58 
59 int nfc_llc_register(const char *name, struct nfc_llc_ops *ops)
60 {
61 	struct nfc_llc_engine *llc_engine;
62 
63 	llc_engine = kzalloc(sizeof(struct nfc_llc_engine), GFP_KERNEL);
64 	if (llc_engine == NULL)
65 		return -ENOMEM;
66 
67 	llc_engine->name = kstrdup(name, GFP_KERNEL);
68 	if (llc_engine->name == NULL) {
69 		kfree(llc_engine);
70 		return -ENOMEM;
71 	}
72 	llc_engine->ops = ops;
73 
74 	INIT_LIST_HEAD(&llc_engine->entry);
75 	list_add_tail (&llc_engine->entry, &llc_engines);
76 
77 	return 0;
78 }
79 
80 static struct nfc_llc_engine *nfc_llc_name_to_engine(const char *name)
81 {
82 	struct nfc_llc_engine *llc_engine;
83 
84 	list_for_each_entry(llc_engine, &llc_engines, entry) {
85 		if (strcmp(llc_engine->name, name) == 0)
86 			return llc_engine;
87 	}
88 
89 	return NULL;
90 }
91 
92 void nfc_llc_unregister(const char *name)
93 {
94 	struct nfc_llc_engine *llc_engine;
95 
96 	llc_engine = nfc_llc_name_to_engine(name);
97 	if (llc_engine == NULL)
98 		return;
99 
100 	list_del(&llc_engine->entry);
101 	kfree(llc_engine->name);
102 	kfree(llc_engine);
103 }
104 
105 struct nfc_llc *nfc_llc_allocate(const char *name, struct nfc_hci_dev *hdev,
106 				 xmit_to_drv_t xmit_to_drv,
107 				 rcv_to_hci_t rcv_to_hci, int tx_headroom,
108 				 int tx_tailroom, llc_failure_t llc_failure)
109 {
110 	struct nfc_llc_engine *llc_engine;
111 	struct nfc_llc *llc;
112 
113 	llc_engine = nfc_llc_name_to_engine(name);
114 	if (llc_engine == NULL)
115 		return NULL;
116 
117 	llc = kzalloc(sizeof(struct nfc_llc), GFP_KERNEL);
118 	if (llc == NULL)
119 		return NULL;
120 
121 	llc->data = llc_engine->ops->init(hdev, xmit_to_drv, rcv_to_hci,
122 					  tx_headroom, tx_tailroom,
123 					  &llc->rx_headroom, &llc->rx_tailroom,
124 					  llc_failure);
125 	if (llc->data == NULL) {
126 		kfree(llc);
127 		return NULL;
128 	}
129 	llc->ops = llc_engine->ops;
130 
131 	return llc;
132 }
133 
134 void nfc_llc_free(struct nfc_llc *llc)
135 {
136 	llc->ops->deinit(llc);
137 	kfree(llc);
138 }
139 
140 inline void nfc_llc_get_rx_head_tail_room(struct nfc_llc *llc, int *rx_headroom,
141 					  int *rx_tailroom)
142 {
143 	*rx_headroom = llc->rx_headroom;
144 	*rx_tailroom = llc->rx_tailroom;
145 }
146 
147 inline int nfc_llc_start(struct nfc_llc *llc)
148 {
149 	return llc->ops->start(llc);
150 }
151 
152 inline int nfc_llc_stop(struct nfc_llc *llc)
153 {
154 	return llc->ops->stop(llc);
155 }
156 
157 inline void nfc_llc_rcv_from_drv(struct nfc_llc *llc, struct sk_buff *skb)
158 {
159 	llc->ops->rcv_from_drv(llc, skb);
160 }
161 
162 inline int nfc_llc_xmit_from_hci(struct nfc_llc *llc, struct sk_buff *skb)
163 {
164 	return llc->ops->xmit_from_hci(llc, skb);
165 }
166 
167 inline void *nfc_llc_get_data(struct nfc_llc *llc)
168 {
169 	return llc->data;
170 }
171