RTAI sample with optimized jitter.
/******************************************************************************
*
* m i n i . c
*
* Minimal module for EtherCAT.
*
* $Id$
*
* 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; version 2 of the License.
*
* 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
*
*****************************************************************************/
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/timer.h>
#include <linux/spinlock.h>
#include <linux/interrupt.h>
#include "../../include/ecrt.h" // EtherCAT realtime interface
#define ASYNC
#define FREQUENCY 100
/*****************************************************************************/
struct timer_list timer;
// EtherCAT
ec_master_t *master = NULL;
ec_domain_t *domain1 = NULL;
spinlock_t master_lock = SPIN_LOCK_UNLOCKED;
// data fields
//void *r_ssi_input, *r_ssi_status, *r_4102[3];
// channels
uint32_t k_pos;
uint8_t k_stat;
ec_field_init_t domain1_fields[] = {
{NULL, "3", "Beckhoff", "EL5001", "InputValue", 0},
{NULL, "2", "Beckhoff", "EL4132", "OutputValue", 0},
{}
};
/*****************************************************************************/
void run(unsigned long data)
{
static unsigned int counter = 0;
spin_lock(&master_lock);
#ifdef ASYNC
// receive
ecrt_master_async_receive(master);
ecrt_domain_process(domain1);
#else
// send and receive
ecrt_domain_queue(domain1);
ecrt_master_run(master);
ecrt_master_sync_io(master);
ecrt_domain_process(domain1);
#endif
// process data
//k_pos = EC_READ_U32(r_ssi);
#ifdef ASYNC
// send
ecrt_domain_queue(domain1);
ecrt_master_run(master);
ecrt_master_async_send(master);
#endif
spin_unlock(&master_lock);
if (counter) {
counter--;
}
else {
counter = FREQUENCY;
//printk(KERN_INFO "k_pos = %i\n", k_pos);
//printk(KERN_INFO "k_stat = 0x%02X\n", k_stat);
}
// restart timer
timer.expires += HZ / FREQUENCY;
add_timer(&timer);
}
/*****************************************************************************/
int request_lock(void *data)
{
spin_lock_bh(&master_lock);
return 0; // access allowed
}
/*****************************************************************************/
void release_lock(void *data)
{
spin_unlock_bh(&master_lock);
}
/*****************************************************************************/
int __init init_mini_module(void)
{
printk(KERN_INFO "=== Starting Minimal EtherCAT environment... ===\n");
if ((master = ecrt_request_master(0)) == NULL) {
printk(KERN_ERR "Requesting master 0 failed!\n");
goto out_return;
}
ecrt_master_callbacks(master, request_lock, release_lock, NULL);
printk(KERN_INFO "Registering domain...\n");
if (!(domain1 = ecrt_master_create_domain(master)))
{
printk(KERN_ERR "Domain creation failed!\n");
goto out_release_master;
}
printk(KERN_INFO "Registering domain fields...\n");
if (ecrt_domain_register_field_list(domain1, domain1_fields)) {
printk(KERN_ERR "Field registration failed!\n");
goto out_release_master;
}
printk(KERN_INFO "Activating master...\n");
if (ecrt_master_activate(master)) {
printk(KERN_ERR "Failed to activate master!\n");
goto out_release_master;
}
#if 0
if (ecrt_master_fetch_sdo_lists(master)) {
printk(KERN_ERR "Failed to fetch SDO lists!\n");
goto out_deactivate;
}
ecrt_master_print(master, 2);
#else
ecrt_master_print(master, 0);
#endif
#if 0
if (!(slave = ecrt_master_get_slave(master, "5"))) {
printk(KERN_ERR "Failed to get slave 5!\n");
goto out_deactivate;
}
if (ecrt_slave_sdo_write_exp8(slave, 0x4061, 1, 0) ||
ecrt_slave_sdo_write_exp8(slave, 0x4061, 2, 1) ||
ecrt_slave_sdo_write_exp8(slave, 0x4061, 3, 1) ||
ecrt_slave_sdo_write_exp8(slave, 0x4066, 0, 0) ||
ecrt_slave_sdo_write_exp8(slave, 0x4067, 0, 4) ||
ecrt_slave_sdo_write_exp8(slave, 0x4068, 0, 0) ||
ecrt_slave_sdo_write_exp8(slave, 0x4069, 0, 25) ||
ecrt_slave_sdo_write_exp8(slave, 0x406A, 0, 25) ||
ecrt_slave_sdo_write_exp8(slave, 0x406B, 0, 50)) {
printk(KERN_ERR "Failed to configure SSI slave!\n");
goto out_deactivate;
}
#endif
#if 0
printk(KERN_INFO "Writing alias...\n");
if (ecrt_slave_sdo_write_exp16(slave, 0xBEEF)) {
printk(KERN_ERR "Failed to write alias!\n");
goto out_deactivate;
}
#endif
#ifdef ASYNC
// send once and wait...
ecrt_master_prepare_async_io(master);
#endif
#if 1
if (ecrt_master_start_eoe(master)) {
printk(KERN_ERR "Failed to start EoE processing!\n");
goto out_deactivate;
}
#endif
printk("Starting cyclic sample thread.\n");
init_timer(&timer);
timer.function = run;
timer.expires = jiffies + 10;
add_timer(&timer);
printk(KERN_INFO "=== Minimal EtherCAT environment started. ===\n");
return 0;
#if 1
out_deactivate:
ecrt_master_deactivate(master);
#endif
out_release_master:
ecrt_release_master(master);
out_return:
return -1;
}
/*****************************************************************************/
void __exit cleanup_mini_module(void)
{
printk(KERN_INFO "=== Stopping Minimal EtherCAT environment... ===\n");
if (master) {
del_timer_sync(&timer);
printk(KERN_INFO "Deactivating master...\n");
ecrt_master_deactivate(master);
ecrt_release_master(master);
}
printk(KERN_INFO "=== Minimal EtherCAT environment stopped. ===\n");
}
/*****************************************************************************/
MODULE_LICENSE("GPL");
MODULE_AUTHOR ("Florian Pose <fp@igh-essen.com>");
MODULE_DESCRIPTION ("EtherCAT minimal test environment");
module_init(init_mini_module);
module_exit(cleanup_mini_module);
/*****************************************************************************/