Added a few docs.
/******************************************************************************
*
* $Id$
*
* Copyright (C) 2006 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
* as published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* 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 right to use EtherCAT Technology is granted and comes free of
* charge under condition of compatibility of product made by
* Licensee. People intending to distribute/sell products based on the
* code, have to sign an agreement to guarantee that products using
* software based on IgH EtherCAT master stay compatible with the actual
* EtherCAT specification (which are released themselves as an open
* standard) as the (only) precondition to have the right to use EtherCAT
* Technology, IP and trade marks.
*
*****************************************************************************/
/**
\file
EtherCAT process data object methods.
*/
/*****************************************************************************/
#include <linux/slab.h>
#include "pdo.h"
/*****************************************************************************/
/** Pdo constructor.
*/
void ec_pdo_init(
ec_pdo_t *pdo /**< EtherCAT Pdo */
)
{
pdo->sync_index = -1; // not assigned
pdo->name = NULL;
INIT_LIST_HEAD(&pdo->entries);
pdo->default_config = 0;
}
/*****************************************************************************/
/** Pdo copy constructor.
*/
int ec_pdo_init_copy(ec_pdo_t *pdo, const ec_pdo_t *other_pdo)
{
pdo->dir = other_pdo->dir;
pdo->index = other_pdo->index;
pdo->sync_index = other_pdo->sync_index;
pdo->name = NULL;
INIT_LIST_HEAD(&pdo->entries);
pdo->default_config = other_pdo->default_config;
if (ec_pdo_set_name(pdo, other_pdo->name))
goto out_return;
if (ec_pdo_copy_entries(pdo, other_pdo))
goto out_clear;
return 0;
out_clear:
ec_pdo_clear(pdo);
out_return:
return -1;
}
/*****************************************************************************/
/** Pdo destructor.
*/
void ec_pdo_clear(ec_pdo_t *pdo /**< EtherCAT Pdo. */)
{
if (pdo->name)
kfree(pdo->name);
ec_pdo_clear_entries(pdo);
}
/*****************************************************************************/
/** Clear Pdo entry list.
*/
void ec_pdo_clear_entries(ec_pdo_t *pdo /**< EtherCAT Pdo. */)
{
ec_pdo_entry_t *entry, *next;
// free all Pdo entries
list_for_each_entry_safe(entry, next, &pdo->entries, list) {
list_del(&entry->list);
ec_pdo_entry_clear(entry);
kfree(entry);
}
}
/*****************************************************************************/
/** Set Pdo name.
*/
int ec_pdo_set_name(
ec_pdo_t *pdo, /**< Pdo. */
const char *name /**< New name. */
)
{
unsigned int len;
if (pdo->name)
kfree(pdo->name);
if (name && (len = strlen(name))) {
if (!(pdo->name = (char *) kmalloc(len + 1, GFP_KERNEL))) {
EC_ERR("Failed to allocate Pdo name.\n");
return -1;
}
memcpy(pdo->name, name, len + 1);
} else {
pdo->name = NULL;
}
return 0;
}
/*****************************************************************************/
/** Add a new Pdo entry to the configuration.
*/
ec_pdo_entry_t *ec_pdo_add_entry(
ec_pdo_t *pdo,
uint16_t index,
uint8_t subindex,
uint8_t bit_length
)
{
ec_pdo_entry_t *entry;
if (!(entry = kmalloc(sizeof(ec_pdo_entry_t), GFP_KERNEL))) {
EC_ERR("Failed to allocate memory for Pdo entry.\n");
return NULL;
}
ec_pdo_entry_init(entry);
entry->index = index;
entry->subindex = subindex;
entry->bit_length = bit_length;
list_add_tail(&entry->list, &pdo->entries);
return entry;
}
/*****************************************************************************/
/** Copy Pdo entries from another Pdo.
*/
int ec_pdo_copy_entries(ec_pdo_t *pdo, const ec_pdo_t *other)
{
ec_pdo_entry_t *entry, *other_entry;
ec_pdo_clear_entries(pdo);
list_for_each_entry(other_entry, &other->entries, list) {
if (!(entry = (ec_pdo_entry_t *)
kmalloc(sizeof(ec_pdo_entry_t), GFP_KERNEL))) {
EC_ERR("Failed to allocate memory for Pdo entry copy.\n");
return -1;
}
if (ec_pdo_entry_init_copy(entry, other_entry)) {
kfree(entry);
return -1;
}
list_add_tail(&entry->list, &pdo->entries);
}
return 0;
}
/*****************************************************************************/
/** Compares the entries of two Pdos.
*
* \retval 1 The entries of the given Pdos are equal.
* \retval 0 The entries of the given Pdos differ.
*/
int ec_pdo_equal_entries(
const ec_pdo_t *pdo1, /**< First Pdo. */
const ec_pdo_t *pdo2 /**< Second Pdo. */
)
{
const struct list_head *head1, *head2, *item1, *item2;
const ec_pdo_entry_t *entry1, *entry2;
head1 = item1 = &pdo1->entries;
head2 = item2 = &pdo2->entries;
while (1) {
item1 = item1->next;
item2 = item2->next;
if ((item1 == head1) ^ (item2 == head2)) // unequal lengths
return 0;
if (item1 == head1) // both finished
break;
entry1 = list_entry(item1, ec_pdo_entry_t, list);
entry2 = list_entry(item2, ec_pdo_entry_t, list);
if (!ec_pdo_entry_equal(entry1, entry2))
return 0;
}
return 1;
}
/*****************************************************************************/
/** Pdo entry constructor.
*/
void ec_pdo_entry_init(
ec_pdo_entry_t *entry /**< Pdo entry. */
)
{
entry->name = NULL;
}
/*****************************************************************************/
/** Pdo entry copy constructor.
*/
int ec_pdo_entry_init_copy(
ec_pdo_entry_t *entry, /**< Pdo entry. */
const ec_pdo_entry_t *other /**< Pdo entry to copy from. */
)
{
entry->index = other->index;
entry->subindex = other->subindex;
entry->name = NULL;
entry->bit_length = other->bit_length;
if (ec_pdo_entry_set_name(entry, other->name))
return -1;
return 0;
}
/*****************************************************************************/
/** Pdo entry destructor.
*/
void ec_pdo_entry_clear(ec_pdo_entry_t *entry /**< Pdo entry. */)
{
if (entry->name)
kfree(entry->name);
}
/*****************************************************************************/
/** Set Pdo entry name.
*/
int ec_pdo_entry_set_name(
ec_pdo_entry_t *entry, /**< Pdo entry. */
const char *name /**< New name. */
)
{
unsigned int len;
if (entry->name)
kfree(entry->name);
if (name && (len = strlen(name))) {
if (!(entry->name = (char *) kmalloc(len + 1, GFP_KERNEL))) {
EC_ERR("Failed to allocate Pdo entry name.\n");
return -1;
}
memcpy(entry->name, name, len + 1);
} else {
entry->name = NULL;
}
return 0;
}
/*****************************************************************************/
/** Compares two Pdo entries.
*
* \retval 1 The entries are equal.
* \retval 0 The entries differ.
*/
int ec_pdo_entry_equal(
const ec_pdo_entry_t *entry1, /**< First Pdo entry. */
const ec_pdo_entry_t *entry2 /**< Second Pdo entry. */
)
{
return entry1->index == entry2->index
&& entry1->subindex == entry2->subindex
&& entry1->bit_length == entry2->bit_length;
}
/*****************************************************************************/