net/nfc/hci/llc.c

   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 }