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, 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 }