nes-proj/cpu/mc1322x/lib/include/i2c.h

135 lines
4.4 KiB
C

/*
* Copyright (c) 2011, Hedde Bosman <heddebosman@incas3.eu>
*
* I2C communication device drivers for mc1322x
*
* 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.
*
*/
#ifndef I2C_H
#define I2C_H
#include <stdint.h>
#include "isr.h"
#include "gpio.h"
#define I2C_NON_BLOCKING 1
/* The I2C Interrupt Service Routine */
void i2c_isr (void);
/* Enable the I2C module */
void i2c_enable(void);
/* Disable the I2C module */
void i2c_disable(void);
/* Returns 1 if the I2C bus is active (we or some other device are transferring data) */
uint8_t i2c_busy(void);
/* Returns 1 if our data is sent or received */
uint8_t i2c_transferred(void); // indicates success of data last transfer (send or receive)
/* start receiving data from 'slave_address' of length 'byte_ctr' and store it in 'rx_buf'
* @parameter slave_addr 7bits (and will be padded with the 'receive bit')
* @parameter byte_ctr the number of bytes expected to be received
* @parameter rx_buf the buffer in which the received bytes will be stored.
*
* IFDEF I2C_NON_BLOCKING THEN THIS FUNCTION RETURNS IMMEDIATLY BUT THE TRANSFER WILL ONLY
* BE COMPLETE WHEN i2c_transferred IS 1
*/
void i2c_receiveinit( uint8_t slave_address, uint8_t byte_ctr, uint8_t *rx_buf);
/* start sending data to 'slave_address' of length 'byte_ctr' found in the buffer 'rx_buf'
* @parameter slave_addr 7bits (and will be padded with the 'send bit')
* @parameter byte_ctr the number of bytes to be sent
* @parameter tx_buf the buffer in which the bytes to be sent are stored
*
* IFDEF I2C_NON_BLOCKING THEN THIS FUNCTION RETURNS IMMEDIATLY BUT THE TRANSFER WILL ONLY
* BE COMPLETE WHEN i2c_transferred IS 1
*/
void i2c_transmitinit(uint8_t slave_address, uint8_t byte_ctr, uint8_t *tx_buf);
#ifndef I2C_NON_BLOCKING
#define I2C_NON_BLOCKING 1
#endif
#if I2C_NON_BLOCKING
uint8_t i2c_receive(void);
void i2c_transmit(void);
#endif
// TODO: see if this is better fit in platform definition
#define I2C_SDA 13 //SDA == P5.1 // GPIO 13
#define I2C_SCL 12 //SCL == P5.2 // GPIO 12
// TODO: this could use a nice struct with bit members...
#define I2C_BASE (0x80006000)
#define I2CADR ((volatile uint8_t *) ( I2C_BASE + 0x00 ))
#define I2CFDR ((volatile uint8_t *) ( I2C_BASE + 0x04 ))
#define I2CCR ((volatile uint8_t *) ( I2C_BASE + 0x08 ))
#define I2CSR ((volatile uint8_t *) ( I2C_BASE + 0x0C ))
#define I2CDR ((volatile uint8_t *) ( I2C_BASE + 0x10 ))
#define I2CDFSRR ((volatile uint8_t *) ( I2C_BASE + 0x14 ))
#define I2CCKER ((volatile uint8_t *) ( I2C_BASE + 0x18 ))
// TODO: fix nice structs
// i2c CR
#define I2C_MEN 0x80
#define I2C_MIEN 0x40
#define I2C_MSTA 0x20
#define I2C_MTX 0x10
#define I2C_TXAK 0x08
#define I2C_RSTA 0x04
#define I2C_BCST 0x01
// i2c SR
#define I2C_MCF 0x80
#define I2C_MAAS 0x40
#define I2C_MBB 0x20
#define I2C_MAL 0x10
#define I2C_BCSTM 0x08
#define I2C_SRW 0x04
#define I2C_MIF 0x02
#define I2C_RXAK 0x01
// i2c digital filter sample rate register
#define I2C_DFSR 0x3f // default = 0x10
// i2c CKER
#define I2C_CKEN 0x01
#endif