master/pdo_list.c
author Patrick Bruenn <p.bruenn@beckhoff.com>
Tue, 12 Apr 2016 11:17:36 +0200
branchstable-1.5
changeset 2654 b3f6b3e5ef29
parent 2522 ec403cf308eb
permissions -rw-r--r--
devices/ccat: revert "limit rx processing to one frame per poll"

revert "limit rx processing to one frame per poll", which caused etherlab
frame timeouts in setups with more than one frame per cycle.
/******************************************************************************
 *
 *  $Id$
 *
 *  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
   EtherCAT PDO list methods.
*/

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

#include <linux/module.h>

#include "globals.h"
#include "pdo.h"
#include "slave_config.h"
#include "master.h"

#include "pdo_list.h"

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

/** PDO list constructor.
 */
void ec_pdo_list_init(
        ec_pdo_list_t *pl /**< PDO list. */
        )
{
    INIT_LIST_HEAD(&pl->list);
}

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

/** PDO list destructor.
 */
void ec_pdo_list_clear(ec_pdo_list_t *pl /**< PDO list. */)
{
    ec_pdo_list_clear_pdos(pl);
}

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

/** Clears the list of mapped PDOs.
 */
void ec_pdo_list_clear_pdos(ec_pdo_list_t *pl /**< PDO list. */)
{
    ec_pdo_t *pdo, *next;

    list_for_each_entry_safe(pdo, next, &pl->list, list) {
        list_del_init(&pdo->list);
        ec_pdo_clear(pdo);
        kfree(pdo);
    }
}

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

/** Calculates the total size of the mapped PDO entries.
 *
 * \retval Data size in byte.
 */
uint16_t ec_pdo_list_total_size(
        const ec_pdo_list_t *pl /**< PDO list. */
        )
{
    unsigned int bit_size;
    const ec_pdo_t *pdo;
    const ec_pdo_entry_t *pdo_entry;
    uint16_t byte_size;

    bit_size = 0;
    list_for_each_entry(pdo, &pl->list, list) {
        list_for_each_entry(pdo_entry, &pdo->entries, list) {
            bit_size += pdo_entry->bit_length;
        }
    }

    if (bit_size % 8) // round up to full bytes
        byte_size = bit_size / 8 + 1;
    else
        byte_size = bit_size / 8;

    return byte_size;
}

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

/** Add a new PDO to the list.
 *
 * \return Pointer to new PDO, otherwise an ERR_PTR() code.
 */
ec_pdo_t *ec_pdo_list_add_pdo(
        ec_pdo_list_t *pl, /**< PDO list. */
        uint16_t index /**< PDO index. */
        )
{
    ec_pdo_t *pdo;

    if (!(pdo = (ec_pdo_t *) kmalloc(sizeof(ec_pdo_t), GFP_KERNEL))) {
        EC_ERR("Failed to allocate memory for PDO.\n");
        return ERR_PTR(-ENOMEM);
    }

    ec_pdo_init(pdo);
    pdo->index = index;
    list_add_tail(&pdo->list, &pl->list);
    return pdo;
}

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

/** Add the copy of an existing PDO to the list.
 *
 * \return 0 on success, else < 0
 */
int ec_pdo_list_add_pdo_copy(
        ec_pdo_list_t *pl, /**< PDO list. */
        const ec_pdo_t *pdo /**< PDO to add. */
        )
{
    ec_pdo_t *mapped_pdo;
    int ret;

    // PDO already mapped?
    list_for_each_entry(mapped_pdo, &pl->list, list) {
        if (mapped_pdo->index != pdo->index) continue;
        EC_ERR("PDO 0x%04X is already mapped!\n", pdo->index);
        return -EEXIST;
    }

    if (!(mapped_pdo = kmalloc(sizeof(ec_pdo_t), GFP_KERNEL))) {
        EC_ERR("Failed to allocate PDO memory.\n");
        return -ENOMEM;
    }

    ret = ec_pdo_init_copy(mapped_pdo, pdo);
    if (ret < 0) {
        kfree(mapped_pdo);
        return ret;
    }

    list_add_tail(&mapped_pdo->list, &pl->list);
    return 0;
}

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

/** Makes a deep copy of another PDO list.
 *
 * \return 0 on success, else < 0
 */
int ec_pdo_list_copy(
        ec_pdo_list_t *pl, /**< PDO list. */
        const ec_pdo_list_t *other /**< PDO list to copy from. */
        )
{
    ec_pdo_t *other_pdo;
    int ret;

    ec_pdo_list_clear_pdos(pl);

    // PDO already mapped?
    list_for_each_entry(other_pdo, &other->list, list) {
        ret = ec_pdo_list_add_pdo_copy(pl, other_pdo);
        if (ret)
            return ret;
    }

    return 0;
}

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

/** Compares two PDO lists.
 *
 * Only the list is compared, not the PDO entries (i. e. the PDO
 * mapping).
 *
 * \retval 1 The given PDO lists are equal.
 * \retval 0 The given PDO lists differ.
 */
int ec_pdo_list_equal(
        const ec_pdo_list_t *pl1, /**< First list. */
        const ec_pdo_list_t *pl2 /**< Second list. */
        )
{
    const struct list_head *h1, *h2, *l1, *l2;
    const ec_pdo_t *p1, *p2;

    h1 = l1 = &pl1->list;
    h2 = l2 = &pl2->list;

    while (1) {
        l1 = l1->next;
        l2 = l2->next;

        if ((l1 == h1) ^ (l2 == h2)) // unequal lengths
            return 0;
        if (l1 == h1) // both finished
            break;

        p1 = list_entry(l1, ec_pdo_t, list);
        p2 = list_entry(l2, ec_pdo_t, list);

        if (p1->index != p2->index)
            return 0;
    }

    return 1;
}

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

/** Finds a PDO with the given index.
 *
 * \return Search result, or NULL.
 */
ec_pdo_t *ec_pdo_list_find_pdo(
        const ec_pdo_list_t *pl, /**< PDO list. */
        uint16_t index /**< PDO index. */
        )
{
    ec_pdo_t *pdo;

    list_for_each_entry(pdo, &pl->list, list) {
        if (pdo->index != index)
            continue;
        return pdo;
    }

    return NULL;
}

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

/** Finds a PDO with the given index and returns a const pointer.
 *
 * \return Search result, or NULL.
 */
const ec_pdo_t *ec_pdo_list_find_pdo_const(
        const ec_pdo_list_t *pl, /**< PDO list. */
        uint16_t index /**< PDO index. */
        )
{
    const ec_pdo_t *pdo;

    list_for_each_entry(pdo, &pl->list, list) {
        if (pdo->index != index)
            continue;
        return pdo;
    }

    return NULL;
}

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

/** Finds a PDO via its position in the list.
 *
 * Const version.
 *
 * \return Zero on success, otherwise a negative error code.
 */
const ec_pdo_t *ec_pdo_list_find_pdo_by_pos_const(
        const ec_pdo_list_t *pl, /**< PDO list. */
        unsigned int pos /**< Position in the list. */
        )
{
    const ec_pdo_t *pdo;

    list_for_each_entry(pdo, &pl->list, list) {
        if (pos--)
            continue;
        return pdo;
    }

    return NULL;
}

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

/** Get the number of PDOs in the list.
 *
 * \return Number of PDOs.
 */
unsigned int ec_pdo_list_count(
        const ec_pdo_list_t *pl /**< PDO list. */
        )
{
    const ec_pdo_t *pdo;
    unsigned int num = 0;

    list_for_each_entry(pdo, &pl->list, list) {
        num++;
    }

    return num;
}

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

/** Outputs the PDOs in the list.
 */
void ec_pdo_list_print(
        const ec_pdo_list_t *pl /**< PDO list. */
        )
{
    const ec_pdo_t *pdo;

    if (list_empty(&pl->list)) {
        printk("(none)");
    } else {
        list_for_each_entry(pdo, &pl->list, list) {
            printk("0x%04X", pdo->index);
            if (pdo->list.next != &pl->list)
                printk(" ");
        }
    }
}

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