kernel/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, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19 #include <linux/types.h>
  20
  21 #include "llc.h"
  22
  23 struct llc_nop {
  24         struct nfc_hci_dev *hdev;
  25         xmit_to_drv_t xmit_to_drv;
  26         rcv_to_hci_t rcv_to_hci;
  27         int tx_headroom;
  28         int tx_tailroom;
  29         llc_failure_t llc_failure;
  30 };
  31
  32 static void *llc_nop_init(struct nfc_hci_dev *hdev, xmit_to_drv_t xmit_to_drv,
  33                           rcv_to_hci_t rcv_to_hci, int tx_headroom,
  34                           int tx_tailroom, int *rx_headroom, int *rx_tailroom,
  35                           llc_failure_t llc_failure)
  36 {
  37         struct llc_nop *llc_nop;
  38
  39         *rx_headroom = 0;
  40         *rx_tailroom = 0;
  41
  42         llc_nop = kzalloc(sizeof(struct llc_nop), GFP_KERNEL);
  43         if (llc_nop == NULL)
  44                 return NULL;
  45
  46         llc_nop->hdev = hdev;
  47         llc_nop->xmit_to_drv = xmit_to_drv;
  48         llc_nop->rcv_to_hci = rcv_to_hci;
  49         llc_nop->tx_headroom = tx_headroom;
  50         llc_nop->tx_tailroom = tx_tailroom;
  51         llc_nop->llc_failure = llc_failure;
  52
  53         return llc_nop;
  54 }
  55
  56 static void llc_nop_deinit(struct nfc_llc *llc)
  57 {
  58         kfree(nfc_llc_get_data(llc));
  59 }
  60
  61 static int llc_nop_start(struct nfc_llc *llc)
  62 {
  63         return 0;
  64 }
  65
  66 static int llc_nop_stop(struct nfc_llc *llc)
  67 {
  68         return 0;
  69 }
  70
  71 static void llc_nop_rcv_from_drv(struct nfc_llc *llc, struct sk_buff *skb)
  72 {
  73         struct llc_nop *llc_nop = nfc_llc_get_data(llc);
  74
  75         llc_nop->rcv_to_hci(llc_nop->hdev, skb);
  76 }
  77
  78 static int llc_nop_xmit_from_hci(struct nfc_llc *llc, struct sk_buff *skb)
  79 {
  80         struct llc_nop *llc_nop = nfc_llc_get_data(llc);
  81
  82         return llc_nop->xmit_to_drv(llc_nop->hdev, skb);
  83 }
  84
  85 static struct nfc_llc_ops llc_nop_ops = {
  86         .init = llc_nop_init,
  87         .deinit = llc_nop_deinit,
  88         .start = llc_nop_start,
  89         .stop = llc_nop_stop,
  90         .rcv_from_drv = llc_nop_rcv_from_drv,
  91         .xmit_from_hci = llc_nop_xmit_from_hci,
  92 };
  93
  94 int nfc_llc_nop_register(void)
  95 {
  96         return nfc_llc_register(LLC_NOP_NAME, &llc_nop_ops);
  97 }