osd-contiki/platform/osd-merkur/dev/i2c.c
2014-06-21 21:30:48 +02:00

392 lines
9.2 KiB
C

/*
* Copyright (c) 2014, Ingo Gulyas Intembsys
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* This file is part of the Contiki operating system.
*
*/
/**
* \file
* I2C driver for ATMEGA128rfa1
*
* \author
* Ingo Gulyas Intembsys
* office@intembsys.at
* www.intembsys.at
*/
#include "i2c.h"
#include "contiki-conf.h"
#include <stdint.h>
#include <avr/power.h>
#include <stdbool.h>
#include <stddef.h>
#if I2C_TD != 0
#include <stdio.h>
#include <avr/pgmspace.h>
#include "system_mgmt.h"
#define PRINTD(FORMAT,args...) {sleep_acquire_lock(); printf_P(PSTR(FORMAT),##args); sleep_release_lock();}
#else
#define PRINTD(...)
#endif
#if WITH_RTDEBUG == 1
#include "rtdebug.h"
#define RTDEBUG_PUSH(x) rtdebug_push(x)
#else
#warning "I2C Driver compiling without RTDEBUG!"
#define RTDEBUG_PUSH(x)
#endif
#ifndef TIMEOUT_TIMER
#warning "I2C Driver compiling without TIMEOUT!"
#endif
static int8_t wait_job();
static int8_t wait_stop();
static int8_t i2c_ioctl(const i2c_driver* const me, uint8_t cmd, uint8_t arg);
static int8_t i2c_read(const i2c_driver* const me, uint8_t cmd_flags, uint8_t* buffer, uint8_t len);
static int8_t i2c_write(const i2c_driver* const me, uint8_t cmd_flags, const uint8_t* data, uint8_t len);
// static linkage of member functions
i2c_driver i2c_drv = {i2c_ioctl, i2c_read, i2c_write};
// lock spi if driver opened to prevent further opening access
static volatile bool i2c_lock = false;
///////////////////////////////////////////////////////////////
// global functions
///////////////////////////////////////////////////////////////
i2c_driver* i2c_open(void)
{
if(i2c_lock == true)
{
RTDEBUG_PUSH(RTDEBUG_CODE__I2C_OPEN__DEVICE_BUSY);
return NULL;
}
i2c_lock = true;
power_twi_enable();
I2C_INIT();
TWBR = I2C_FREQ_STANDARD;
TWSR &= ~((1<<TWPS1) | (1<<TWPS0));
TWSR |= (1<<TWPS0);
TWCR = (1<<TWEN);
return &i2c_drv;
}
void i2c_close(i2c_driver* const me)
{
if(me == NULL || i2c_lock == false)
{
RTDEBUG_PUSH(RTDEBUG_CODE__I2C_CLOSE__NO_DEVICE);
return;
}
i2c_reset();
return;
}
void i2c_reset(void)
{
TWCR &= ~(1<<TWEN);
I2C_DEINIT();
power_twi_disable();
i2c_lock = false;
return;
}
///////////////////////////////////////////////////////////////
// local helper functions
///////////////////////////////////////////////////////////////
#ifdef TIMEOUT_TIMER
static int8_t wait_job()
{
int8_t status = I2C_OK;
uint16_t timeout = TIMEOUT_TIMER_NOW_ADD(I2C_TIMEOUT);
while (!(TWCR & (1<<TWINT)))
{
if(!(TIMEOUT_TIMER_LT(TIMEOUT_TIMER_NOW(), timeout)))
{
status = I2C_ERROR_TIMEOUT;
break;
}
}
return status;
}
static int8_t wait_stop()
{
int8_t status = I2C_OK;
uint16_t timeout = TIMEOUT_TIMER_NOW_ADD(I2C_TIMEOUT);
while (TWCR & (1<<TWSTO))
{
if(!(TIMEOUT_TIMER_LT(TIMEOUT_TIMER_NOW(), timeout)))
{
status = I2C_ERROR_TIMEOUT;
break;
}
}
return status;
}
#else
static int8_t wait_job()
{
while (!(TWCR & (1<<TWINT)));
return I2C_OK;
}
static int8_t wait_stop()
{
while (TWCR & (1<<TWSTO));
return I2C_OK;
}
#endif
///////////////////////////////////////////////////////////////
// member functions
///////////////////////////////////////////////////////////////
static int8_t i2c_ioctl(const i2c_driver* const me, uint8_t cmd, uint8_t arg)
{
if(me == NULL || i2c_lock == false)
{
RTDEBUG_PUSH(RTDEBUG_CODE__I2C_IOCTL__DEVICE_CLOSED);
return I2C_ERROR_DRIVER;
}
if(cmd == I2C_IOCTL_CMD_SET_FREQ)
{
switch(arg)
{
case I2C_FREQ_400KHZ: TWBR = I2C_FREQ_400KHZ; break;
case I2C_FREQ_250KHZ: TWBR = I2C_FREQ_250KHZ; break;
case I2C_FREQ_100KHZ: TWBR = I2C_FREQ_100KHZ; break;
case I2C_FREQ_50KHZ: TWBR = I2C_FREQ_50KHZ; break;
case I2C_FREQ_10KHZ: TWBR = I2C_FREQ_10KHZ; break;
default:
{
RTDEBUG_PUSH(RTDEBUG_CODE__I2C_IOCTL__ARG_INVALID);
return I2C_ERROR_DRIVER;
}
}
}
else
{
RTDEBUG_PUSH(RTDEBUG_CODE__I2C_IOCTL__CMD_INVALID);
return I2C_ERROR_DRIVER;
}
return I2C_OK;
}
static int8_t i2c_read(const i2c_driver* const me, uint8_t cmd_flags, uint8_t* buffer, uint8_t len)
{
uint8_t i = 0;
int8_t status = I2C_OK;
if(me == NULL || i2c_lock == false)
{
RTDEBUG_PUSH(RTDEBUG_CODE__I2C_READ__DEVICE_CLOSED);
return I2C_ERROR_DRIVER;
}
if((len > 0) && (buffer == NULL))
{
RTDEBUG_PUSH(RTDEBUG_CODE__I2C_READ__ERROR_NULLPOINTER);
return I2C_ERROR_DRIVER;
}
do
{
if(cmd_flags & I2C_CMD_FLAG_START)
{
I2C_START();
if(wait_job() != I2C_OK)
{
RTDEBUG_PUSH(RTDEBUG_CODE__I2C_READ__START_TIMEOUT);
status = I2C_ERROR_TIMEOUT;
break;
}
if((I2C_STATUS() != I2C_STATUS_START) && (I2C_STATUS() != I2C_STATUS_START_REP))
{
RTDEBUG_PUSH(RTDEBUG_CODE__I2C_READ__START_ERROR);
status = I2C_ERROR_START;
break;
}
PRINTD("I2C-RD-START\n");
}
if(len == 0) break;
for(i=0; i<(len-1); i++)
{
I2C_READ_BYTE_ACK();
if(wait_job() != I2C_OK)
{
RTDEBUG_PUSH(RTDEBUG_CODE__I2C_READ__READ_BYTE_ACK_TIMEOUT);
status = I2C_ERROR_TIMEOUT;
break;
}
if(I2C_STATUS() != I2C_STATUS_DATAR_ACK)
{
RTDEBUG_PUSH(RTDEBUG_CODE__I2C_READ__READ_BYTE_ACK_ERROR);
status = I2C_ERROR_READ;
break;
}
buffer[i] = I2C_RX_REG;
PRINTD("I2C-RD-RACK: 0x%02X\n", buffer[i]);
}
I2C_READ_BYTE_NACK();
if(wait_job() != I2C_OK)
{
RTDEBUG_PUSH(RTDEBUG_CODE__I2C_READ__READ_BYTE_NACK_TIMEOUT);
status = I2C_ERROR_TIMEOUT;
break;
}
if(I2C_STATUS() != I2C_STATUS_DATAR_NACK)
{
RTDEBUG_PUSH(RTDEBUG_CODE__I2C_READ__READ_BYTE_NACK_ERROR);
status = I2C_ERROR_READ;
break;
}
buffer[i] = I2C_RX_REG;
PRINTD("I2C-RD-RNACK: 0x%02X\n", buffer[i]);
} while (0);
if(cmd_flags & I2C_CMD_FLAG_STOP)
{
I2C_STOP();
if(wait_stop() != I2C_OK)
{
RTDEBUG_PUSH(RTDEBUG_CODE__I2C_READ__STOP_TIMEOUT);
status = I2C_ERROR_TIMEOUT;
}
PRINTD("I2C-RD_STOP\n");
}
return status;
}
static int8_t i2c_write(const i2c_driver* const me, uint8_t cmd_flags, const uint8_t* data, uint8_t len)
{
uint8_t i = 0;
int8_t status = I2C_OK;
if(me == NULL || i2c_lock == false)
{
RTDEBUG_PUSH(RTDEBUG_CODE__I2C_WRITE__DEVICE_CLOSED);
return I2C_ERROR_DRIVER;
}
if((len > 0) && (data == NULL))
{
RTDEBUG_PUSH(RTDEBUG_CODE__I2C_WRITE__ERROR_NULLPOINTER);
return I2C_ERROR_DRIVER;
}
do
{
if(cmd_flags & I2C_CMD_FLAG_START)
{
I2C_START();
if(wait_job() != I2C_OK)
{
RTDEBUG_PUSH(RTDEBUG_CODE__I2C_WRITE__START_TIMEOUT);
status = I2C_ERROR_TIMEOUT;
break;
}
if((I2C_STATUS() != I2C_STATUS_START) && (I2C_STATUS() != I2C_STATUS_START_REP))
{
RTDEBUG_PUSH(RTDEBUG_CODE__I2C_WRITE__START_ERROR);
status = I2C_ERROR_START;
break;
}
PRINTD("I2C-WR-START\n");
}
for(i=0; i<len; i++)
{
I2C_TX_REG = data[i];
I2C_WRITE_BYTE();
if(wait_job() != I2C_OK)
{
RTDEBUG_PUSH(RTDEBUG_CODE__I2C_WRITE__WRITE_BYTE_TIMEOUT);
status = I2C_ERROR_TIMEOUT;
break;
}
if((I2C_STATUS() != I2C_STATUS_DATAW_ACK) && (I2C_STATUS() != I2C_STATUS_SLAW_ACK) && (I2C_STATUS() != I2C_STATUS_SLAR_ACK))
{
RTDEBUG_PUSH(RTDEBUG_CODE__I2C_WRITE__WRITE_BYTE_ERROR);
status = I2C_ERROR_WRITE;
break;
}
PRINTD("I2C-WR-BYTE: 0x%02X\n", data[i]);
}
} while (0);
if(cmd_flags & I2C_CMD_FLAG_STOP)
{
I2C_STOP();
if(wait_stop() != I2C_OK)
{
RTDEBUG_PUSH(RTDEBUG_CODE__I2C_WRITE__STOP_TIMEOUT);
status = I2C_ERROR_TIMEOUT;
}
PRINTD("I2C-WR-STOP\n");
}
return status;
}