net/nfc/hci/llc_nop.c

   1 /*
   2  * nop (passthrough) Link Layer Control
   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 <linux/types.h>
  22
  23 #include "llc.h"
  24
  25 struct llc_nop {
  26         struct nfc_hci_dev *hdev;
  27         xmit_to_drv_t xmit_to_drv;
  28         rcv_to_hci_t rcv_to_hci;
  29         int tx_headroom;
  30         int tx_tailroom;
  31         llc_failure_t llc_failure;
  32 };
  33
  34 static void *llc_nop_init(struct nfc_hci_dev *hdev, xmit_to_drv_t xmit_to_drv,
  35                           rcv_to_hci_t rcv_to_hci, int tx_headroom,
  36                           int tx_tailroom, int *rx_headroom, int *rx_tailroom,
  37                           llc_failure_t llc_failure)
  38 {
  39         struct llc_nop *llc_nop;
  40
  41         *rx_headroom = 0;
  42         *rx_tailroom = 0;
  43
  44         llc_nop = kzalloc(sizeof(struct llc_nop), GFP_KERNEL);
  45         if (llc_nop == NULL)
  46                 return NULL;
  47
  48         llc_nop->hdev = hdev;
  49         llc_nop->xmit_to_drv = xmit_to_drv;
  50         llc_nop->rcv_to_hci = rcv_to_hci;
  51         llc_nop->tx_headroom = tx_headroom;
  52         llc_nop->tx_tailroom = tx_tailroom;
  53         llc_nop->llc_failure = llc_failure;
  54
  55         return llc_nop;
  56 }
  57
  58 static void llc_nop_deinit(struct nfc_llc *llc)
  59 {
  60         kfree(nfc_llc_get_data(llc));
  61 }
  62
  63 static int llc_nop_start(struct nfc_llc *llc)
  64 {
  65         return 0;
  66 }
  67
  68 static int llc_nop_stop(struct nfc_llc *llc)
  69 {
  70         return 0;
  71 }
  72
  73 static void llc_nop_rcv_from_drv(struct nfc_llc *llc, struct sk_buff *skb)
  74 {
  75         struct llc_nop *llc_nop = nfc_llc_get_data(llc);
  76
  77         llc_nop->rcv_to_hci(llc_nop->hdev, skb);
  78 }
  79
  80 static int llc_nop_xmit_from_hci(struct nfc_llc *llc, struct sk_buff *skb)
  81 {
  82         struct llc_nop *llc_nop = nfc_llc_get_data(llc);
  83
  84         return llc_nop->xmit_to_drv(llc_nop->hdev, skb);
  85 }
  86
  87 static struct nfc_llc_ops llc_nop_ops = {
  88         .init = llc_nop_init,
  89         .deinit = llc_nop_deinit,
  90         .start = llc_nop_start,
  91         .stop = llc_nop_stop,
  92         .rcv_from_drv = llc_nop_rcv_from_drv,
  93         .xmit_from_hci = llc_nop_xmit_from_hci,
  94 };
  95
  96 int nfc_llc_nop_register(void)
  97 {
  98         return nfc_llc_register(LLC_NOP_NAME, &llc_nop_ops);
  99 }