Added missing documentation.
/******************************************************************************
*
* RTAI sample for the IgH EtherCAT master.
*
* $Id$
*
* 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.
*
*****************************************************************************/
// Linux
#include <linux/module.h>
// RTAI
#include "rtai_sched.h"
#include "rtai_sem.h"
// EtherCAT
#include "../../include/ecrt.h"
/*****************************************************************************/
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Florian Pose <fp@igh-essen.com>");
MODULE_DESCRIPTION("EtherCAT RTAI sample module");
/*****************************************************************************/
// comment this for synchronous IO
#define ASYNC
// RTAI task frequency in Hz
#define FREQUENCY 10000
#define TIMERTICKS (1000000000 / FREQUENCY)
/*****************************************************************************/
// RTAI
RT_TASK task;
SEM master_sem;
cycles_t t_last_start = 0;
cycles_t t_critical;
// EtherCAT
ec_master_t *master = NULL;
ec_domain_t *domain1 = NULL;
// data fields
void *r_ssi_input;
// channels
uint32_t k_pos;
ec_field_init_t domain1_fields[] = {
{&r_ssi_input, "3", "Beckhoff", "EL5001", "InputValue", 0},
{NULL, "2", "Beckhoff", "EL4132", "OutputValue", 0},
{}
};
/*****************************************************************************/
void run(long data)
{
while (1)
{
t_last_start = get_cycles();
rt_sem_wait(&master_sem);
#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_input);
#ifdef ASYNC
// send
ecrt_domain_queue(domain1);
ecrt_master_run(master);
ecrt_master_async_send(master);
#endif
rt_sem_signal(&master_sem);
rt_task_wait_period();
}
}
/*****************************************************************************/
int request_lock(void *data)
{
// too close to the next RT cycle: deny access...
if (get_cycles() - t_last_start > t_critical) return -1;
// allow access
rt_sem_wait(&master_sem);
return 0;
}
/*****************************************************************************/
void release_lock(void *data)
{
rt_sem_signal(&master_sem);
}
/*****************************************************************************/
int __init init_mod(void)
{
RTIME tick_period, requested_ticks, now;
printk(KERN_INFO "=== Starting EtherCAT RTAI sample module... ===\n");
rt_sem_init(&master_sem, 1);
t_critical = cpu_khz * 800 / FREQUENCY; // ticks for 80%
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 (ecrt_master_start_eoe(master)) {
printk(KERN_ERR "Failed to start EoE processing!\n");
goto out_deactivate;
}
printk("Starting cyclic sample thread...\n");
requested_ticks = nano2count(TIMERTICKS);
tick_period = start_rt_timer(requested_ticks);
printk(KERN_INFO "RT timer started with %i/%i ticks.\n",
(int) tick_period, (int) requested_ticks);
if (rt_task_init(&task, run, 0, 2000, 0, 1, NULL)) {
printk(KERN_ERR "Failed to init RTAI task!\n");
goto out_stop_timer;
}
now = rt_get_time();
if (rt_task_make_periodic(&task, now + tick_period, tick_period)) {
printk(KERN_ERR "Failed to run RTAI task!\n");
goto out_stop_task;
}
printk(KERN_INFO "=== EtherCAT RTAI sample module started. ===\n");
return 0;
out_stop_task:
rt_task_delete(&task);
out_stop_timer:
stop_rt_timer();
out_deactivate:
ecrt_master_deactivate(master);
out_release_master:
ecrt_release_master(master);
out_return:
rt_sem_delete(&master_sem);
return -1;
}
/*****************************************************************************/
void __exit cleanup_mod(void)
{
printk(KERN_INFO "=== Stopping EtherCAT RTAI sample module... ===\n");
rt_task_delete(&task);
stop_rt_timer();
ecrt_master_deactivate(master);
ecrt_release_master(master);
rt_sem_delete(&master_sem);
printk(KERN_INFO "=== EtherCAT RTAI sample module stopped. ===\n");
}
/*****************************************************************************/
module_init(init_mod);
module_exit(cleanup_mod);
/*****************************************************************************/