/******************************************************************************
 *
 *  $Id$
 *
 *  Copyright (C) 2006-2008  Florian Pose, Ingenieurgemeinschaft IgH
 *
 *  This file is part of the IgH EtherCAT Master.
 *
 *  The IgH EtherCAT Master is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU General Public License version 2, as
 *  published by the Free Software Foundation.
 *
 *  The IgH EtherCAT Master 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 the IgH EtherCAT Master; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 *  ---
 *
 *  The license mentioned above concerns the source code only. Using the
 *  EtherCAT technology and brand is only permitted in compliance with the
 *  industrial property and similar rights of Beckhoff Automation GmbH.
 *
 *****************************************************************************/

/**
   \file
   Ethernet over EtherCAT (EoE)
*/

/*****************************************************************************/

#ifndef __EC_ETHERNET_H__
#define __EC_ETHERNET_H__

#include <linux/list.h>
#include <linux/netdevice.h>

#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 27)
#include <linux/semaphore.h>
#else
#include <asm/semaphore.h>
#endif

#include "globals.h"
#include "slave.h"
#include "datagram.h"

/*****************************************************************************/

/**
   Queued frame structure.
*/

typedef struct
{
    struct list_head queue; /**< list item */
    struct sk_buff *skb; /**< socket buffer */
}
ec_eoe_frame_t;

/*****************************************************************************/

typedef struct ec_eoe ec_eoe_t; /**< \see ec_eoe */

/**
   Ethernet over EtherCAT (EoE) handler.
   The master creates one of these objects for each slave that supports the
   EoE protocol.
*/

struct ec_eoe
{
    struct list_head list; /**< list item */
    ec_slave_t *slave; /**< pointer to the corresponding slave */
    ec_datagram_t datagram; /**< datagram */
    unsigned int queue_datagram; /**< the datagram is ready for queuing */
    void (*state)(ec_eoe_t *); /**< state function for the state machine */
    struct net_device *dev; /**< net_device for virtual ethernet device */
    struct net_device_stats stats; /**< device statistics */
    unsigned int opened; /**< net_device is opened */
    unsigned long rate_jiffies; /**< time of last rate output */

    struct sk_buff *rx_skb; /**< current rx socket buffer */
    off_t rx_skb_offset; /**< current write pointer in the socket buffer */
    size_t rx_skb_size; /**< size of the allocated socket buffer memory */
    uint8_t rx_expected_fragment; /**< next expected fragment number */
    uint32_t rx_counter; /**< octets received during last second */
    uint32_t rx_rate; /**< receive rate (bps) */
    unsigned int rx_idle; /**< Idle flag. */

    struct list_head tx_queue; /**< queue for frames to send */
    unsigned int tx_queue_size; /**< Transmit queue size. */
    unsigned int tx_queue_active; /**< kernel netif queue started */
    unsigned int tx_queued_frames; /**< number of frames in the queue */
    struct semaphore tx_queue_sem; /**< Semaphore for the send queue. */
    ec_eoe_frame_t *tx_frame; /**< current TX frame */
    uint8_t tx_frame_number; /**< number of the transmitted frame */
    uint8_t tx_fragment_number; /**< number of the fragment */
    size_t tx_offset; /**< number of octets sent */
    uint32_t tx_counter; /**< octets transmitted during last second */
    uint32_t tx_rate; /**< transmit rate (bps) */
    unsigned int tx_idle; /**< Idle flag. */

    unsigned int tries; /**< Tries. */
};

/*****************************************************************************/

int ec_eoe_init(ec_eoe_t *, ec_slave_t *);
void ec_eoe_clear(ec_eoe_t *);
void ec_eoe_run(ec_eoe_t *);
void ec_eoe_queue(ec_eoe_t *);
int ec_eoe_is_open(const ec_eoe_t *);
int ec_eoe_is_idle(const ec_eoe_t *);

/*****************************************************************************/

#endif

/*****************************************************************************/