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

     2

 *

     3

 *  $Id$

     4

 *

     5

 *  Copyright (C) 2006-2008  Florian Pose, Ingenieurgemeinschaft IgH

     6

 *

     7

 *  This file is part of the IgH EtherCAT Master.

     8

 *

     9

 *  The IgH EtherCAT Master is free software; you can redistribute it and/or

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 *  modify it under the terms of the GNU General Public License version 2, as

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 *  published by the Free Software Foundation.

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 *

    13

 *  The IgH EtherCAT Master is distributed in the hope that it will be useful,

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 *  but WITHOUT ANY WARRANTY; without even the implied warranty of

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 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General

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 *  Public License for more details.

    17

 *

    18

 *  You should have received a copy of the GNU General Public License along

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 *  with the IgH EtherCAT Master; if not, write to the Free Software

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 *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

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 *

    22

 *  ---

    23

 *

    24

 *  The license mentioned above concerns the source code only. Using the

    25

 *  EtherCAT technology and brand is only permitted in compliance with the

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 *  industrial property and similar rights of Beckhoff Automation GmbH.

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 *

    28

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

    29

    30

/**

    31

   \file

    32

   Ethernet over EtherCAT (EoE).

    33

*/

    34

    35

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

    36

    37

#include <linux/version.h>

    38

#include <linux/netdevice.h>

    39

#include <linux/etherdevice.h>

    40

    41

#include "globals.h"

    42

#include "master.h"

    43

#include "slave.h"

    44

#include "mailbox.h"

    45

#include "ethernet.h"

    46

    47

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

    48

    49

/** Defines the debug level of EoE processing.

    50

 *

    51

 * 0 = No debug messages.

    52

 * 1 = Output warnings.

    53

 * 2 = Output actions.

    54

 * 3 = Output actions and frame data.

    55

 */

    56

#define EOE_DEBUG_LEVEL 1

    57

    58

/** Size of the EoE tx queue.

    59

 */

    60

#define EC_EOE_TX_QUEUE_SIZE 100

    61

    62

/** Number of tries.

    63

 */

    64

#define EC_EOE_TRIES 100

    65

    66

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

    67

    68

void ec_eoe_flush(ec_eoe_t *);

    69

    70

// state functions

    71

void ec_eoe_state_rx_start(ec_eoe_t *);

    72

void ec_eoe_state_rx_check(ec_eoe_t *);

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void ec_eoe_state_rx_fetch(ec_eoe_t *);

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void ec_eoe_state_tx_start(ec_eoe_t *);

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void ec_eoe_state_tx_sent(ec_eoe_t *);

    76

    77

// net_device functions

    78

int ec_eoedev_open(struct net_device *);

    79

int ec_eoedev_stop(struct net_device *);

    80

int ec_eoedev_tx(struct sk_buff *, struct net_device *);

    81

struct net_device_stats *ec_eoedev_stats(struct net_device *);

    82

    83

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

    84

    85

#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 29)

    86

/** Device operations for EoE interfaces.

    87

 */

    88

static const struct net_device_ops ec_eoedev_ops = {

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    .ndo_open = ec_eoedev_open,

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    .ndo_stop = ec_eoedev_stop,

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    .ndo_start_xmit = ec_eoedev_tx,

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    .ndo_get_stats = ec_eoedev_stats,

    93

};

    94

#endif

    95

    96

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

    97

    98

/** EoE constructor.

    99

 *

   100

 * Initializes the EoE handler, creates a net_device and registers it.

   101

 *

   102

 * \return Zero on success, otherwise a negative error code.

   103

 */

   104

int ec_eoe_init(

   105

        ec_eoe_t *eoe, /**< EoE handler */

   106

        ec_slave_t *slave /**< EtherCAT slave */

   107

        )

   108

{

   109

    ec_eoe_t **priv;

   110

    int i, ret = 0;

   111

    char name[EC_DATAGRAM_NAME_SIZE];

   112

   113

    eoe->slave = slave;

   114

   115

    ec_datagram_init(&eoe->datagram);

   116

    eoe->queue_datagram = 0;

   117

    eoe->state = ec_eoe_state_rx_start;

   118

    eoe->opened = 0;

   119

    eoe->rx_skb = NULL;

   120

    eoe->rx_expected_fragment = 0;

   121

    INIT_LIST_HEAD(&eoe->tx_queue);

   122

    eoe->tx_frame = NULL;

   123

    eoe->tx_queue_active = 0;

   124

    eoe->tx_queue_size = EC_EOE_TX_QUEUE_SIZE;

   125

    eoe->tx_queued_frames = 0;

   126

   127

    sema_init(&eoe->tx_queue_sem, 1);

   128

    eoe->tx_frame_number = 0xFF;

   129

    memset(&eoe->stats, 0, sizeof(struct net_device_stats));

   130

   131

    eoe->rx_counter = 0;

   132

    eoe->tx_counter = 0;

   133

    eoe->rx_rate = 0;

   134

    eoe->tx_rate = 0;

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    eoe->rate_jiffies = 0;

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    eoe->rx_idle = 1;

   137

    eoe->tx_idle = 1;

   138

   139

    /* device name eoe<MASTER>[as]<SLAVE>, because networking scripts don't

   140

     * like hyphens etc. in interface names. */

   141

    if (slave->effective_alias) {

   142

        snprintf(name, EC_DATAGRAM_NAME_SIZE,

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                "eoe%ua%u", slave->master->index, slave->effective_alias);

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    } else {

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        snprintf(name, EC_DATAGRAM_NAME_SIZE,

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                "eoe%us%u", slave->master->index, slave->ring_position);

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    }

   148

   149

    snprintf(eoe->datagram.name, EC_DATAGRAM_NAME_SIZE, name);

   150

   151

    if (!(eoe->dev = alloc_netdev(sizeof(ec_eoe_t *), name, ether_setup))) {

   152

        EC_SLAVE_ERR(slave, "Unable to allocate net_device %s"

   153

                " for EoE handler!\n", name);

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        ret = -ENODEV;

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        goto out_return;

   156

    }

   157

   158

    // initialize net_device

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#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 29)

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    eoe->dev->netdev_ops = &ec_eoedev_ops;

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#else

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    eoe->dev->open = ec_eoedev_open;

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    eoe->dev->stop = ec_eoedev_stop;

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    eoe->dev->hard_start_xmit = ec_eoedev_tx;

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    eoe->dev->get_stats = ec_eoedev_stats;

   166

#endif

   167

   168

    for (i = 0; i < ETH_ALEN; i++)

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        eoe->dev->dev_addr[i] = i | (i << 4);

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   171

    // initialize private data

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    priv = netdev_priv(eoe->dev);

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    *priv = eoe;

   174

   175

    // Usually setting the MTU appropriately makes the upper layers

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    // do the frame fragmenting. In some cases this doesn't work

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    // so the MTU is left on the Ethernet standard value and fragmenting

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    // is done "manually".

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#if 0

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    eoe->dev->mtu = slave->configured_rx_mailbox_size - ETH_HLEN - 10;

   181

#endif

   182

   183

    // connect the net_device to the kernel

   184

    ret = register_netdev(eoe->dev);

   185

    if (ret) {

   186

        EC_SLAVE_ERR(slave, "Unable to register net_device:"

   187

                " error %i\n", ret);

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        goto out_free;

   189

    }

   190

   191

    // make the last address octet unique

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    eoe->dev->dev_addr[ETH_ALEN - 1] = (uint8_t) eoe->dev->ifindex;

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    return 0;

   194

   195

 out_free:

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    free_netdev(eoe->dev);

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    eoe->dev = NULL;

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 out_return:

   199

    return ret;

   200

}

   201

   202

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

   203

   204

/** EoE destructor.

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 *

   206

 * Unregisteres the net_device and frees allocated memory.

   207

 */

   208

void ec_eoe_clear(ec_eoe_t *eoe /**< EoE handler */)

   209

{

   210

    unregister_netdev(eoe->dev); // possibly calls close callback

   211

   212

    // empty transmit queue

   213

    ec_eoe_flush(eoe);

   214

   215

    if (eoe->tx_frame) {

   216

        dev_kfree_skb(eoe->tx_frame->skb);

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        kfree(eoe->tx_frame);

   218

    }

   219

   220

    if (eoe->rx_skb)

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        dev_kfree_skb(eoe->rx_skb);

   222

   223

    free_netdev(eoe->dev);

   224

   225

    ec_datagram_clear(&eoe->datagram);

   226

}

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   228

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

   229

   230

/** Empties the transmit queue.

   231

 */

   232

void ec_eoe_flush(ec_eoe_t *eoe /**< EoE handler */)

   233

{

   234

    ec_eoe_frame_t *frame, *next;

   235

   236

    down(&eoe->tx_queue_sem);

   237

   238

    list_for_each_entry_safe(frame, next, &eoe->tx_queue, queue) {

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        list_del(&frame->queue);

   240

        dev_kfree_skb(frame->skb);

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        kfree(frame);

   242

    }

   243

    eoe->tx_queued_frames = 0;

   244

   245

    up(&eoe->tx_queue_sem);

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}

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   248

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

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   250

/** Sends a frame or the next fragment.

   251

 *

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 * \return Zero on success, otherwise a negative error code.

   253

 */

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int ec_eoe_send(ec_eoe_t *eoe /**< EoE handler */)

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{

   256

    size_t remaining_size, current_size, complete_offset;

   257

    unsigned int last_fragment;

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    uint8_t *data;

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#if EOE_DEBUG_LEVEL >= 3

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    unsigned int i;

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#endif

   262

   263

    remaining_size = eoe->tx_frame->skb->len - eoe->tx_offset;

   264

   265

    if (remaining_size <= eoe->slave->configured_tx_mailbox_size - 10) {

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        current_size = remaining_size;

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        last_fragment = 1;

   268

    } else {

   269

        current_size = ((eoe->slave->configured_tx_mailbox_size - 10) / 32) * 32;

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        last_fragment = 0;

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    }

   272

   273

    if (eoe->tx_fragment_number) {

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        complete_offset = eoe->tx_offset / 32;

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    }

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    else {

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        // complete size in 32 bit blocks, rounded up.

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        complete_offset = remaining_size / 32 + 1;

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    }

   280

   281

#if EOE_DEBUG_LEVEL >= 2

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    EC_SLAVE_DBG(slave, 0, "EoE %s TX sending fragment %u%s"

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            " with %u octets (%u). %u frames queued.\n",

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            eoe->dev->name, eoe->tx_fragment_number,

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            last_fragment ? "" : "+", current_size, complete_offset,

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            eoe->tx_queued_frames);

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#endif

   288

   289

#if EOE_DEBUG_LEVEL >= 3

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    EC_SLAVE_DBG(master, 0, "");

   291

    for (i = 0; i < current_size; i++) {

   292

        printk("%02X ", eoe->tx_frame->skb->data[eoe->tx_offset + i]);

   293

        if ((i + 1) % 16 == 0) {

   294

            printk("\n");

   295

            EC_SLAVE_DBG(master, 0, "");

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        }

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    }

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    printk("\n");

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#endif

   300

   301

    data = ec_slave_mbox_prepare_send(eoe->slave, &eoe->datagram,

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            0x02, current_size + 4);

   303

    if (IS_ERR(data))

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        return PTR_ERR(data);

   305

   306

    EC_WRITE_U8 (data,     0x00); // eoe fragment req.

   307

    EC_WRITE_U8 (data + 1, last_fragment);

   308

    EC_WRITE_U16(data + 2, ((eoe->tx_fragment_number & 0x3F) |

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                            (complete_offset & 0x3F) << 6 |

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                            (eoe->tx_frame_number & 0x0F) << 12));

   311

   312

    memcpy(data + 4, eoe->tx_frame->skb->data + eoe->tx_offset, current_size);

   313

    eoe->queue_datagram = 1;

   314

   315

    eoe->tx_offset += current_size;

   316

    eoe->tx_fragment_number++;

   317

    return 0;

   318

}

   319

   320

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

   321

   322

/** Runs the EoE state machine.

   323

 */

   324

void ec_eoe_run(ec_eoe_t *eoe /**< EoE handler */)

   325

{

   326

    if (!eoe->opened)

   327

        return;

   328

   329

    // if the datagram was not sent, or is not yet received, skip this cycle

   330

    if (eoe->queue_datagram || eoe->datagram.state == EC_DATAGRAM_SENT)

   331

        return;

   332

   333

    // call state function

   334

    eoe->state(eoe);

   335

   336

    // update statistics

   337

    if (jiffies - eoe->rate_jiffies > HZ) {

   338

        eoe->rx_rate = eoe->rx_counter;

   339

        eoe->tx_rate = eoe->tx_counter;

   340

        eoe->rx_counter = 0;

   341

        eoe->tx_counter = 0;

   342

        eoe->rate_jiffies = jiffies;

   343

    }

   344

   345

    ec_datagram_output_stats(&eoe->datagram);

   346

}

   347

   348

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

   349

   350

/** Queues the datagram, if necessary.

   351

 */

   352

void ec_eoe_queue(ec_eoe_t *eoe /**< EoE handler */)

   353

{

   354

   if (eoe->queue_datagram) {

   355

       ec_master_queue_datagram_ext(eoe->slave->master, &eoe->datagram);

   356

       eoe->queue_datagram = 0;

   357

   }

   358

}

   359

   360

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

   361

   362

/** Returns the state of the device.

   363

 *

   364

 * \return 1 if the device is "up", 0 if it is "down"

   365

 */

   366

int ec_eoe_is_open(const ec_eoe_t *eoe /**< EoE handler */)

   367

{

   368

    return eoe->opened;

   369

}

   370

   371

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

   372

   373

/** Returns the idle state.

   374

 *

   375

 * \retval 1 The device is idle.

   376

 * \retval 0 The device is busy.

   377

 */

   378

int ec_eoe_is_idle(const ec_eoe_t *eoe /**< EoE handler */)

   379

{

   380

    return eoe->rx_idle && eoe->tx_idle;

   381

}

   382

   383

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

   384

 *  STATE PROCESSING FUNCTIONS

   385

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

   386

   387

/** State: RX_START.

   388

 *

   389

 * Starts a new receiving sequence by queueing a datagram that checks the

   390

 * slave's mailbox for a new EoE datagram.

   391

 *

   392

 * \todo Use both devices.

   393

 */

   394

void ec_eoe_state_rx_start(ec_eoe_t *eoe /**< EoE handler */)

   395

{

   396

    if (eoe->slave->error_flag ||

   397

            !eoe->slave->master->devices[EC_DEVICE_MAIN].link_state) {

   398

        eoe->rx_idle = 1;

   399

        eoe->tx_idle = 1;

   400

        return;

   401

    }

   402

   403

    ec_slave_mbox_prepare_check(eoe->slave, &eoe->datagram);

   404

    eoe->queue_datagram = 1;

   405

    eoe->state = ec_eoe_state_rx_check;

   406

}

   407

   408

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

   409

   410

/** State: RX_CHECK.

   411

 *

   412

 * Processes the checking datagram sent in RX_START and issues a receive

   413

 * datagram, if new data is available.

   414

 */

   415

void ec_eoe_state_rx_check(ec_eoe_t *eoe /**< EoE handler */)

   416

{

   417

    if (eoe->datagram.state != EC_DATAGRAM_RECEIVED) {

   418

        eoe->stats.rx_errors++;

   419

#if EOE_DEBUG_LEVEL >= 1

   420

        EC_SLAVE_WARN(eoe->slave, "Failed to receive mbox"

   421

                " check datagram for %s.\n", eoe->dev->name);

   422

#endif

   423

        eoe->state = ec_eoe_state_tx_start;

   424

        return;

   425

    }

   426

   427

    if (!ec_slave_mbox_check(&eoe->datagram)) {

   428

        eoe->rx_idle = 1;

   429

        eoe->state = ec_eoe_state_tx_start;

   430

        return;

   431

    }

   432

   433

    eoe->rx_idle = 0;

   434

    ec_slave_mbox_prepare_fetch(eoe->slave, &eoe->datagram);

   435

    eoe->queue_datagram = 1;

   436

    eoe->state = ec_eoe_state_rx_fetch;

   437

}

   438

   439

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

   440

   441

/** State: RX_FETCH.

   442

 *

   443

 * Checks if the requested data of RX_CHECK was received and processes the EoE

   444

 * datagram.

   445

 */

   446

void ec_eoe_state_rx_fetch(ec_eoe_t *eoe /**< EoE handler */)

   447

{

   448

    size_t rec_size, data_size;

   449

    uint8_t *data, frame_type, last_fragment, time_appended, mbox_prot;

   450

    uint8_t fragment_offset, fragment_number;

   451

#if EOE_DEBUG_LEVEL >= 2

   452

    uint8_t frame_number;

   453

#endif

   454

    off_t offset;

   455

#if EOE_DEBUG_LEVEL >= 3

   456

    unsigned int i;

   457

#endif

   458

   459

    if (eoe->datagram.state != EC_DATAGRAM_RECEIVED) {

   460

        eoe->stats.rx_errors++;

   461

#if EOE_DEBUG_LEVEL >= 1

   462

        EC_SLAVE_WARN(eoe->slave, "Failed to receive mbox"

   463

                " fetch datagram for %s.\n", eoe->dev->name);

   464

#endif

   465

        eoe->state = ec_eoe_state_tx_start;

   466

        return;

   467

    }

   468

   469

    data = ec_slave_mbox_fetch(eoe->slave, &eoe->datagram,

   470

            &mbox_prot, &rec_size);

   471

    if (IS_ERR(data)) {

   472

        eoe->stats.rx_errors++;

   473

#if EOE_DEBUG_LEVEL >= 1

   474

        EC_SLAVE_WARN(eoe->slave, "Invalid mailbox response for %s.\n",

   475

                eoe->dev->name);

   476

#endif

   477

        eoe->state = ec_eoe_state_tx_start;

   478

        return;

   479

    }

   480

   481

    if (mbox_prot != 0x02) { // EoE FIXME mailbox handler necessary

   482

        eoe->stats.rx_errors++;

   483

#if EOE_DEBUG_LEVEL >= 1

   484

        EC_SLAVE_WARN(eoe->slave, "Other mailbox protocol response for %s.\n",