llc.c

Go to the documentation of this file.

/*
 * Link Layer Control manager
 *
 * Copyright (C) 2012  Intel Corporation. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the
 * Free Software Foundation, Inc.,
 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

#include <net/nfc/llc.h>

#include "llc.h"

static struct list_head llc_engines;

int nfc_llc_init(void)
{
    int r;

    INIT_LIST_HEAD(&llc_engines);

    r = nfc_llc_nop_register();
    if (r)
        goto exit;

    r = nfc_llc_shdlc_register();
    if (r)
        goto exit;

    return 0;

exit:
    nfc_llc_exit();
    return r;
}

void nfc_llc_exit(void)
{
    struct nfc_llc_engine *llc_engine, *n;

    list_for_each_entry_safe(llc_engine, n, &llc_engines, entry) {
        list_del(&llc_engine->entry);
        kfree(llc_engine->name);
        kfree(llc_engine);
    }
}

int nfc_llc_register(const char *name, struct nfc_llc_ops *ops)
{
    struct nfc_llc_engine *llc_engine;

    llc_engine = kzalloc(sizeof(struct nfc_llc_engine), GFP_KERNEL);
    if (llc_engine == NULL)
        return -ENOMEM;

    llc_engine->name = kstrdup(name, GFP_KERNEL);
    if (llc_engine->name == NULL) {
        kfree(llc_engine);
        return -ENOMEM;
    }
    llc_engine->ops = ops;

    INIT_LIST_HEAD(&llc_engine->entry);
    list_add_tail (&llc_engine->entry, &llc_engines);

    return 0;
}

static struct nfc_llc_engine *nfc_llc_name_to_engine(const char *name)
{
    struct nfc_llc_engine *llc_engine;

    list_for_each_entry(llc_engine, &llc_engines, entry) {
        if (strcmp(llc_engine->name, name) == 0)
            return llc_engine;
    }

    return NULL;
}

void nfc_llc_unregister(const char *name)
{
    struct nfc_llc_engine *llc_engine;

    llc_engine = nfc_llc_name_to_engine(name);
    if (llc_engine == NULL)
        return;

    list_del(&llc_engine->entry);
    kfree(llc_engine->name);
    kfree(llc_engine);
}

struct nfc_llc *nfc_llc_allocate(const char *name, struct nfc_hci_dev *hdev,
                 xmit_to_drv_t xmit_to_drv,
                 rcv_to_hci_t rcv_to_hci, int tx_headroom,
                 int tx_tailroom, llc_failure_t llc_failure)
{
    struct nfc_llc_engine *llc_engine;
    struct nfc_llc *llc;

    llc_engine = nfc_llc_name_to_engine(name);
    if (llc_engine == NULL)
        return NULL;

    llc = kzalloc(sizeof(struct nfc_llc), GFP_KERNEL);
    if (llc == NULL)
        return NULL;

    llc->data = llc_engine->ops->init(hdev, xmit_to_drv, rcv_to_hci,
                      tx_headroom, tx_tailroom,
                      &llc->rx_headroom, &llc->rx_tailroom,
                      llc_failure);
    if (llc->data == NULL) {
        kfree(llc);
        return NULL;
    }
    llc->ops = llc_engine->ops;

    return llc;
}

void nfc_llc_free(struct nfc_llc *llc)
{
    llc->ops->deinit(llc);
    kfree(llc);
}

inline void nfc_llc_get_rx_head_tail_room(struct nfc_llc *llc, int *rx_headroom,
                      int *rx_tailroom)
{
    *rx_headroom = llc->rx_headroom;
    *rx_tailroom = llc->rx_tailroom;
}

inline int nfc_llc_start(struct nfc_llc *llc)
{
    return llc->ops->start(llc);
}

inline int nfc_llc_stop(struct nfc_llc *llc)
{
    return llc->ops->stop(llc);
}

inline void nfc_llc_rcv_from_drv(struct nfc_llc *llc, struct sk_buff *skb)
{
    llc->ops->rcv_from_drv(llc, skb);
}

inline int nfc_llc_xmit_from_hci(struct nfc_llc *llc, struct sk_buff *skb)
{
    return llc->ops->xmit_from_hci(llc, skb);
}

inline void *nfc_llc_get_data(struct nfc_llc *llc)
{
    return llc->data;
}