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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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 *

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 *  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

    19

 *  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

    21

 *

    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.

    27

 *

    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 *);

    73

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 *);

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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 = {

    89

    .ndo_open = ec_eoedev_open,

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    .ndo_stop = ec_eoedev_stop,

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    .ndo_start_xmit = ec_eoedev_tx,

    92

    .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

int ec_eoe_init(

   103

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

   104

        ec_slave_t *slave /**< EtherCAT slave */

   105

        )

   106

{

   107

    ec_eoe_t **priv;

   108

    int i, ret = 0;

   109

    char name[EC_DATAGRAM_NAME_SIZE];

   110

   111

    eoe->slave = slave;

   112

   113

    ec_datagram_init(&eoe->datagram);

   114

    ec_mbox_init(&eoe->mbox,&eoe->datagram);

   115

    eoe->queue_datagram = 0;

   116

    eoe->state = ec_eoe_state_rx_start;

   117

    eoe->opened = 0;

   118

    eoe->rx_skb = NULL;

   119

    eoe->rx_expected_fragment = 0;

   120

    INIT_LIST_HEAD(&eoe->tx_queue);

   121

    eoe->tx_frame = NULL;

   122

    eoe->tx_queue_active = 0;

   123

    eoe->tx_queue_size = EC_EOE_TX_QUEUE_SIZE;

   124

    eoe->tx_queued_frames = 0;

   125

   126

    ec_mutex_init(&eoe->tx_queue_mutex);

   127

    eoe->tx_frame_number = 0xFF;

   128

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

   129

   130

    eoe->rx_counter = 0;

   131

    eoe->tx_counter = 0;

   132

    eoe->rx_rate = 0;

   133

    eoe->tx_rate = 0;

   134

    eoe->rate_jiffies = 0;

   135

    eoe->rx_idle = 1;

   136

    eoe->tx_idle = 1;

   137

   138

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

   139

     * like hyphens etc. in interface names. */

   140

    if (slave->effective_alias) {

   141

        snprintf(name, EC_DATAGRAM_NAME_SIZE,

   142

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

   143

    } else {

   144

        snprintf(name, EC_DATAGRAM_NAME_SIZE,

   145

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

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    }

   147

   148

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

   149

   150

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

   151

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

   152

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

   153

        ret = -ENODEV;

   154

        goto out_return;

   155

    }

   156

   157

    // initialize net_device

   158

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

   159

    eoe->dev->netdev_ops = &ec_eoedev_ops;

   160

#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;

   165

#endif

   166

   167

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

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

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   170

    // initialize private data

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    priv = netdev_priv(eoe->dev);

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    *priv = eoe;

   173

   174

    // 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;

   180

#endif

   181

   182

    // connect the net_device to the kernel

   183

    ret = register_netdev(eoe->dev);

   184

    if (ret) {

   185

        EC_SLAVE_ERR(slave, "Unable to register net_device:"

   186

                " error %i\n", ret);

   187

        goto out_free;

   188

    }

   189

   190

    // 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;

   193

   194

 out_free:

   195

    free_netdev(eoe->dev);

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    eoe->dev = NULL;

   197

 out_return:

   198

    return ret;

   199

}

   200

   201

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

   202

   203

/** EoE destructor.

   204

 *

   205

 * Unregisteres the net_device and frees allocated memory.

   206

 */

   207

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

   208

{

   209

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

   210

   211

    // empty transmit queue

   212

    ec_eoe_flush(eoe);

   213

   214

    if (eoe->tx_frame) {

   215

        dev_kfree_skb(eoe->tx_frame->skb);

   216

        kfree(eoe->tx_frame);

   217

    }

   218

   219

    if (eoe->rx_skb)

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        dev_kfree_skb(eoe->rx_skb);

   221

   222

    free_netdev(eoe->dev);

   223

   224

    ec_mbox_clear(&eoe->mbox);

   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

    ec_mutex_lock(&eoe->tx_queue_mutex);

   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);

   241

        kfree(frame);

   242

    }

   243

    eoe->tx_queued_frames = 0;

   244

   245

    ec_mutex_unlock(&eoe->tx_queue_mutex);

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

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{

   254

    size_t remaining_size, current_size, complete_offset;

   255

    unsigned int last_fragment;

   256

    uint8_t *data;

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#if EOE_DEBUG_LEVEL >= 3

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    unsigned int i;

   259

#endif

   260

   261

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

   262

   263

    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;

   266

    } else {

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

   268

        last_fragment = 0;

   269

    }

   270

   271

    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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    }

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   279

#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

   286

   287

#if EOE_DEBUG_LEVEL >= 3

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    EC_SLAVE_DBG(master, 0, "");

   289

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

   290

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

   291

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

   292

            printk("\n");

   293

            EC_SLAVE_DBG(master, 0, "");

   294

        }

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    }

   296

    printk("\n");

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#endif

   298

   299

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

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            0x02, current_size + 4);

   301

    if (IS_ERR(data))

   302

        return PTR_ERR(data);

   303

   304

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

   305

    EC_WRITE_U8 (data + 1, last_fragment);

   306

    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));

   309

   310

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

   311

    eoe->queue_datagram = 1;

   312

   313

    eoe->tx_offset += current_size;

   314

    eoe->tx_fragment_number++;

   315

    return 0;

   316

}

   317

   318

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

   319

   320

/** Runs the EoE state machine.

   321

 */

   322

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

   323

{

   324

    if (!eoe->opened)

   325

        return;

   326

   327

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

   328

    if (eoe->queue_datagram ||

   329

        ec_mbox_is_datagram_state(&eoe->mbox, EC_DATAGRAM_QUEUED) ||

   330

        ec_mbox_is_datagram_state(&eoe->mbox, EC_DATAGRAM_SENT)) {

   331

        return;

   332

    }

   333

   334

    // call state function

   335

    eoe->state(eoe);

   336

   337

    // update statistics

   338

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

   339

        eoe->rx_rate = eoe->rx_counter;

   340

        eoe->tx_rate = eoe->tx_counter;

   341

        eoe->rx_counter = 0;

   342

        eoe->tx_counter = 0;

   343

        eoe->rate_jiffies = jiffies;

   344

    }

   345

   346

    ec_datagram_output_stats(&eoe->datagram);

   347

}

   348

   349

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

   350

   351

/** Queues the datagram, if necessary.

   352

 */

   353

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

   354

{

   355

   if (eoe->queue_datagram) {

   356

       ec_master_mbox_queue_datagrams(eoe->slave->master, &eoe->mbox);

   357

       eoe->queue_datagram = 0;

   358

   }

   359

}

   360

   361

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

   362

   363

/** Returns the state of the device.

   364

 *

   365

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

   366

 */

   367

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

   368

{

   369

    return eoe->opened;

   370

}

   371

   372

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

   373

   374

/** Returns the idle state.

   375

 *

   376

 * \retval 1 The device is idle.

   377

 * \retval 0 The device is busy.

   378

 */

   379

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

   380

{

   381

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

   382

}

   383

   384

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

   385

 *  STATE PROCESSING FUNCTIONS

   386

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

   387

   388

/** State: RX_START.

   389

 *

   390

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

   391

 * slave's mailbox for a new EoE datagram.

   392

 */

   393

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

   394

{

   395

    if (eoe->slave->error_flag ||

   396

            !eoe->slave->master->main_device.link_state) {

   397

        eoe->rx_idle = 1;

   398

        eoe->tx_idle = 1;

   399

        return;

   400

    }

   401

   402

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

   403

    eoe->queue_datagram = 1;

   404

    eoe->state = ec_eoe_state_rx_check;

   405

}

   406

   407

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

   408

   409

/** State: RX_CHECK.

   410

 *

   411

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

   412

 * datagram, if new data is available.

   413

 */

   414

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

   415

{

   416

    if (!ec_mbox_is_datagram_state(&eoe->mbox, EC_DATAGRAM_RECEIVED)) {

   417

        eoe->stats.rx_errors++;

   418

#if EOE_DEBUG_LEVEL >= 1

   419

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

   420

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

   421

#endif

   422

        eoe->state = ec_eoe_state_tx_start;

   423

        return;

   424

    }

   425

   426

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

   427

        eoe->rx_idle = 1;

   428

        eoe->state = ec_eoe_state_tx_start;

   429

        return;

   430

    }

   431

   432

    eoe->rx_idle = 0;

   433

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

   434

    eoe->queue_datagram = 1;

   435

    eoe->state = ec_eoe_state_rx_fetch;

   436

}

   437

   438

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

   439

   440

/** State: RX_FETCH.

   441

 *

   442

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

   443

 * datagram.

   444

 */

   445

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

   446

{

   447

    size_t rec_size, data_size;

   448

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

   449

    uint8_t frame_number, fragment_offset, fragment_number;

   450

    off_t offset;

   451

#if EOE_DEBUG_LEVEL >= 3

   452

    unsigned int i;

   453

#endif

   454

   455

    if (!ec_mbox_is_datagram_state(&eoe->mbox, EC_DATAGRAM_RECEIVED)) {

   456

        eoe->stats.rx_errors++;

   457

#if EOE_DEBUG_LEVEL >= 1

   458

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

   459

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

   460

#endif

   461

        eoe->state = ec_eoe_state_tx_start;

   462

        return;

   463

    }

   464

   465

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

   466

            &mbox_prot, &rec_size);

   467

    if (IS_ERR(data)) {

   468

        eoe->stats.rx_errors++;

   469

#if EOE_DEBUG_LEVEL >= 1

   470

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

   471

                eoe->dev->name);

   472

#endif

   473

        eoe->state = ec_eoe_state_tx_start;

   474

        return;

   475

    }

   476

   477

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

   478

        eoe->stats.rx_errors++;

   479

#if EOE_DEBUG_LEVEL >= 1

   480

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

   481

                eoe->dev->name);

   482

#endif

   483

        eoe->state = ec_eoe_state_tx_start;

   484

        return;