Better slave scan sub state machine.
/******************************************************************************
*
* $Id$
*
* 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
Mailbox functionality.
*/
/*****************************************************************************/
#include <linux/slab.h>
#include <linux/delay.h>
#include "mailbox.h"
#include "datagram.h"
#include "master.h"
/*****************************************************************************/
/**
Prepares a mailbox-send datagram.
\return pointer to mailbox datagram data
*/
uint8_t *ec_slave_mbox_prepare_send(const ec_slave_t *slave, /**< slave */
ec_datagram_t *datagram, /**< datagram */
uint8_t type, /**< mailbox protocol */
size_t size /**< size of the data */
)
{
size_t total_size;
if (unlikely(!slave->sii_mailbox_protocols)) {
EC_ERR("Slave %i does not support mailbox communication!\n",
slave->ring_position);
return NULL;
}
total_size = size + 6;
if (unlikely(total_size > slave->sii_rx_mailbox_size)) {
EC_ERR("Data size does not fit in mailbox!\n");
return NULL;
}
if (ec_datagram_npwr(datagram, slave->station_address,
slave->sii_rx_mailbox_offset,
slave->sii_rx_mailbox_size))
return NULL;
EC_WRITE_U16(datagram->data, size); // mailbox service data length
EC_WRITE_U16(datagram->data + 2, slave->station_address); // station addr.
EC_WRITE_U8 (datagram->data + 4, 0x00); // channel & priority
EC_WRITE_U8 (datagram->data + 5, type); // underlying protocol type
return datagram->data + 6;
}
/*****************************************************************************/
/**
Prepares a datagram for checking the mailbox state.
\return 0 in case of success, else < 0
*/
int ec_slave_mbox_prepare_check(const ec_slave_t *slave, /**< slave */
ec_datagram_t *datagram /**< datagram */
)
{
// FIXME: second sync manager?
if (ec_datagram_nprd(datagram, slave->station_address, 0x808, 8))
return -1;
return 0;
}
/*****************************************************************************/
/**
Processes a mailbox state checking datagram.
\return 0 in case of success, else < 0
*/
int ec_slave_mbox_check(const ec_datagram_t *datagram /**< datagram */)
{
return EC_READ_U8(datagram->data + 5) & 8 ? 1 : 0;
}
/*****************************************************************************/
/**
Prepares a datagram to fetch mailbox data.
\return 0 in case of success, else < 0
*/
int ec_slave_mbox_prepare_fetch(const ec_slave_t *slave, /**< slave */
ec_datagram_t *datagram /**< datagram */
)
{
if (ec_datagram_nprd(datagram, slave->station_address,
slave->sii_tx_mailbox_offset,
slave->sii_tx_mailbox_size)) return -1;
return 0;
}
/*****************************************************************************/
/**
Processes received mailbox data.
\return pointer to the received data
*/
uint8_t *ec_slave_mbox_fetch(const ec_slave_t *slave, /**< slave */
ec_datagram_t *datagram, /**< datagram */
uint8_t type, /**< expected mailbox protocol */
size_t *size /**< size of the received data */
)
{
size_t data_size;
if ((EC_READ_U8(datagram->data + 5) & 0x0F) != type) {
EC_ERR("Unexpected mailbox protocol 0x%02X (exp.: 0x%02X) at"
" slave %i!\n", EC_READ_U8(datagram->data + 5), type,
slave->ring_position);
return NULL;
}
if ((data_size = EC_READ_U16(datagram->data)) >
slave->sii_tx_mailbox_size - 6) {
EC_ERR("Currupt mailbox response detected!\n");
return NULL;
}
*size = data_size;
return datagram->data + 6;
}
/*****************************************************************************/
/**
Sends a mailbox datagram and waits for its reception.
\return pointer to the received data
*/
uint8_t *ec_slave_mbox_simple_io(const ec_slave_t *slave, /**< slave */
ec_datagram_t *datagram, /**< datagram */
size_t *size /**< size of the received data */
)
{
uint8_t type;
type = EC_READ_U8(datagram->data + 5);
if (unlikely(ec_master_simple_io(slave->master, datagram))) {
EC_ERR("Mailbox checking failed on slave %i!\n",
slave->ring_position);
return NULL;
}
return ec_slave_mbox_simple_receive(slave, datagram, type, size);
}
/*****************************************************************************/
/**
Waits for the reception of a mailbox datagram.
\return pointer to the received data
*/
uint8_t *ec_slave_mbox_simple_receive(const ec_slave_t *slave, /**< slave */
ec_datagram_t *datagram, /**< datagram */
uint8_t type, /**< expected protocol */
size_t *size /**< received data size */
)
{
cycles_t start, end, timeout;
start = get_cycles();
timeout = (cycles_t) 100 * cpu_khz; // 100ms
while (1)
{
if (ec_slave_mbox_prepare_check(slave, datagram)) return NULL;
if (unlikely(ec_master_simple_io(slave->master, datagram))) {
EC_ERR("Mailbox checking failed on slave %i!\n",
slave->ring_position);
return NULL;
}
end = get_cycles();
if (ec_slave_mbox_check(datagram))
break; // proceed with receiving data
if ((end - start) >= timeout) {
EC_ERR("Mailbox check - Slave %i timed out.\n",
slave->ring_position);
return NULL;
}
udelay(100);
}
if (ec_slave_mbox_prepare_fetch(slave, datagram)) return NULL;
if (unlikely(ec_master_simple_io(slave->master, datagram))) {
EC_ERR("Mailbox receiving failed on slave %i!\n",
slave->ring_position);
return NULL;
}
if (unlikely(slave->master->debug_level) > 1)
EC_DBG("Mailbox receive took %ius.\n",
((unsigned int) (end - start) * 1000 / cpu_khz));
return ec_slave_mbox_fetch(slave, datagram, type, size);
}
/*****************************************************************************/