net/nfc/hci/llc.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Link Layer Control manager
   4  *
   5  * Copyright (C) 2012  Intel Corporation. All rights reserved.
   6  */
   7
   8 #include <net/nfc/llc.h>
   9
  10 #include "llc.h"
  11
  12 static LIST_HEAD(llc_engines);
  13
  14 int __init nfc_llc_init(void)
  15 {
  16         int r;
  17
  18         r = nfc_llc_nop_register();
  19         if (r)
  20                 goto exit;
  21
  22         r = nfc_llc_shdlc_register();
  23         if (r)
  24                 goto exit;
  25
  26         return 0;
  27
  28 exit:
  29         nfc_llc_exit();
  30         return r;
  31 }
  32
  33 static void nfc_llc_del_engine(struct nfc_llc_engine *llc_engine)
  34 {
  35         list_del(&llc_engine->entry);
  36         kfree_const(llc_engine->name);
  37         kfree(llc_engine);
  38 }
  39
  40 void nfc_llc_exit(void)
  41 {
  42         struct nfc_llc_engine *llc_engine, *n;
  43
  44         list_for_each_entry_safe(llc_engine, n, &llc_engines, entry)
  45                 nfc_llc_del_engine(llc_engine);
  46 }
  47
  48 int nfc_llc_register(const char *name, const struct nfc_llc_ops *ops)
  49 {
  50         struct nfc_llc_engine *llc_engine;
  51
  52         llc_engine = kzalloc(sizeof(struct nfc_llc_engine), GFP_KERNEL);
  53         if (llc_engine == NULL)
  54                 return -ENOMEM;
  55
  56         llc_engine->name = kstrdup_const(name, GFP_KERNEL);
  57         if (llc_engine->name == NULL) {
  58                 kfree(llc_engine);
  59                 return -ENOMEM;
  60         }
  61         llc_engine->ops = ops;
  62
  63         INIT_LIST_HEAD(&llc_engine->entry);
  64         list_add_tail(&llc_engine->entry, &llc_engines);
  65
  66         return 0;
  67 }
  68
  69 static struct nfc_llc_engine *nfc_llc_name_to_engine(const char *name)
  70 {
  71         struct nfc_llc_engine *llc_engine;
  72
  73         list_for_each_entry(llc_engine, &llc_engines, entry) {
  74                 if (strcmp(llc_engine->name, name) == 0)
  75                         return llc_engine;
  76         }
  77
  78         return NULL;
  79 }
  80
  81 void nfc_llc_unregister(const char *name)
  82 {
  83         struct nfc_llc_engine *llc_engine;
  84
  85         llc_engine = nfc_llc_name_to_engine(name);
  86         if (llc_engine == NULL)
  87                 return;
  88
  89         nfc_llc_del_engine(llc_engine);
  90 }
  91
  92 struct nfc_llc *nfc_llc_allocate(const char *name, struct nfc_hci_dev *hdev,
  93                                  xmit_to_drv_t xmit_to_drv,
  94                                  rcv_to_hci_t rcv_to_hci, int tx_headroom,
  95                                  int tx_tailroom, llc_failure_t llc_failure)
  96 {
  97         struct nfc_llc_engine *llc_engine;
  98         struct nfc_llc *llc;
  99
 100         llc_engine = nfc_llc_name_to_engine(name);
 101         if (llc_engine == NULL)
 102                 return NULL;
 103
 104         llc = kzalloc(sizeof(struct nfc_llc), GFP_KERNEL);
 105         if (llc == NULL)
 106                 return NULL;
 107
 108         llc->data = llc_engine->ops->init(hdev, xmit_to_drv, rcv_to_hci,
 109                                           tx_headroom, tx_tailroom,
 110                                           &llc->rx_headroom, &llc->rx_tailroom,
 111                                           llc_failure);
 112         if (llc->data == NULL) {
 113                 kfree(llc);
 114                 return NULL;
 115         }
 116         llc->ops = llc_engine->ops;
 117
 118         return llc;
 119 }
 120
 121 void nfc_llc_free(struct nfc_llc *llc)
 122 {
 123         llc->ops->deinit(llc);
 124         kfree(llc);
 125 }
 126
 127 int nfc_llc_start(struct nfc_llc *llc)
 128 {
 129         return llc->ops->start(llc);
 130 }
 131 EXPORT_SYMBOL(nfc_llc_start);
 132
 133 int nfc_llc_stop(struct nfc_llc *llc)
 134 {
 135         return llc->ops->stop(llc);
 136 }
 137 EXPORT_SYMBOL(nfc_llc_stop);
 138
 139 void nfc_llc_rcv_from_drv(struct nfc_llc *llc, struct sk_buff *skb)
 140 {
 141         llc->ops->rcv_from_drv(llc, skb);
 142 }
 143
 144 int nfc_llc_xmit_from_hci(struct nfc_llc *llc, struct sk_buff *skb)
 145 {
 146         return llc->ops->xmit_from_hci(llc, skb);
 147 }
 148
 149 void *nfc_llc_get_data(struct nfc_llc *llc)
 150 {
 151         return llc->data;
 152 }