net/nfc/hci/llc_nop.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * nop (passthrough) Link Layer Control
   4  *
   5  * Copyright (C) 2012  Intel Corporation. All rights reserved.
   6  */
   7
   8 #include <linux/types.h>
   9
  10 #include "llc.h"
  11
  12 struct llc_nop {
  13         struct nfc_hci_dev *hdev;
  14         xmit_to_drv_t xmit_to_drv;
  15         rcv_to_hci_t rcv_to_hci;
  16         int tx_headroom;
  17         int tx_tailroom;
  18         llc_failure_t llc_failure;
  19 };
  20
  21 static void *llc_nop_init(struct nfc_hci_dev *hdev, xmit_to_drv_t xmit_to_drv,
  22                           rcv_to_hci_t rcv_to_hci, int tx_headroom,
  23                           int tx_tailroom, int *rx_headroom, int *rx_tailroom,
  24                           llc_failure_t llc_failure)
  25 {
  26         struct llc_nop *llc_nop;
  27
  28         *rx_headroom = 0;
  29         *rx_tailroom = 0;
  30
  31         llc_nop = kzalloc(sizeof(struct llc_nop), GFP_KERNEL);
  32         if (llc_nop == NULL)
  33                 return NULL;
  34
  35         llc_nop->hdev = hdev;
  36         llc_nop->xmit_to_drv = xmit_to_drv;
  37         llc_nop->rcv_to_hci = rcv_to_hci;
  38         llc_nop->tx_headroom = tx_headroom;
  39         llc_nop->tx_tailroom = tx_tailroom;
  40         llc_nop->llc_failure = llc_failure;
  41
  42         return llc_nop;
  43 }
  44
  45 static void llc_nop_deinit(struct nfc_llc *llc)
  46 {
  47         kfree(nfc_llc_get_data(llc));
  48 }
  49
  50 static int llc_nop_start(struct nfc_llc *llc)
  51 {
  52         return 0;
  53 }
  54
  55 static int llc_nop_stop(struct nfc_llc *llc)
  56 {
  57         return 0;
  58 }
  59
  60 static void llc_nop_rcv_from_drv(struct nfc_llc *llc, struct sk_buff *skb)
  61 {
  62         struct llc_nop *llc_nop = nfc_llc_get_data(llc);
  63
  64         llc_nop->rcv_to_hci(llc_nop->hdev, skb);
  65 }
  66
  67 static int llc_nop_xmit_from_hci(struct nfc_llc *llc, struct sk_buff *skb)
  68 {
  69         struct llc_nop *llc_nop = nfc_llc_get_data(llc);
  70
  71         return llc_nop->xmit_to_drv(llc_nop->hdev, skb);
  72 }
  73
  74 static const struct nfc_llc_ops llc_nop_ops = {
  75         .init = llc_nop_init,
  76         .deinit = llc_nop_deinit,
  77         .start = llc_nop_start,
  78         .stop = llc_nop_stop,
  79         .rcv_from_drv = llc_nop_rcv_from_drv,
  80         .xmit_from_hci = llc_nop_xmit_from_hci,
  81 };
  82
  83 int nfc_llc_nop_register(void)
  84 {
  85         return nfc_llc_register(LLC_NOP_NAME, &llc_nop_ops);
  86 }