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uboot-1.1.4-kirkwood/board/mv_feroceon/USP/mv_i2c.c
2024-01-09 13:43:28 +01:00

172 lines
4.8 KiB
C

/*******************************************************************************
Copyright (C) Marvell International Ltd. and its affiliates
********************************************************************************
Marvell GPL License Option
If you received this File from Marvell, you may opt to use, redistribute and/or
modify this File in accordance with the terms and conditions of the General
Public License Version 2, June 1991 (the "GPL License"), a copy of which is
available along with the File in the license.txt file or by writing to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 or
on the worldwide web at http://www.gnu.org/licenses/gpl.txt.
THE FILE IS DISTRIBUTED AS-IS, WITHOUT WARRANTY OF ANY KIND, AND THE IMPLIED
WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE ARE EXPRESSLY
DISCLAIMED. The GPL License provides additional details about this warranty
disclaimer.
*******************************************************************************/
#include <common.h>
#include <mpc8xx.h>
#include <malloc.h>
#include <config.h>
#include "twsi/mvTwsi.h"
#if CONFIG_COMMANDS & CFG_CMD_I2C
#define MAX_I2C_RETRYS 10
#define I2C_DELAY 300 /* Should be at least the # of MHz of Tclk */
#undef DEBUG_I2C
//#define DEBUG_I2C
#ifdef DEBUG_I2C
#define DP(x) x
#else
#define DP(x)
#endif
/* Assuming that there is only one master on the bus (us) */
void
i2c_init(MV_U8 chanNum, int speed, int slaveaddr)
{
MV_TWSI_ADDR slave;
slave.type = ADDR7_BIT;
slave.address = slaveaddr;
mvTwsiInit(chanNum, speed, CFG_TCLK, &slave, 0);
}
/*
* Read interface:
* dev_addr:I2C chip address, range 0..127
* offset: Memory (register) address within the chip
* alen: Number of bytes to use for addr (typically 1, 2 for larger
* memories, 0 for register type devices with only one
* register)
* data: Where to read the data
* len: How many bytes to read/write
*
* Returns: 0 on success, not 0 on failure
*/
int
i2c_read(MV_U8 chanNum, MV_U8 dev_addr, unsigned int offset, int alen, MV_U8* data, int len)
{
MV_TWSI_SLAVE twsiSlave;
unsigned int i2cFreq = CFG_I2C_SPEED;
DP(puts("i2c_read\n"));
twsiSlave.slaveAddr.type = ADDR7_BIT;
twsiSlave.slaveAddr.address = dev_addr;
if(alen != 0){
twsiSlave.validOffset = MV_TRUE;
twsiSlave.offset = offset;
if(alen == 2)
{
twsiSlave.moreThen256 = MV_TRUE;
}
else
{
twsiSlave.moreThen256 = MV_FALSE;
}
}
i2c_init(chanNum, i2cFreq,0); /* set the i2c frequency */
return mvTwsiRead (chanNum, &twsiSlave, data, len);
}
/*
* Write interface:
* dev_addr:I2C chip address, range 0..127
* offset: Memory (register) address within the chip
* alen: Number of bytes to use for addr (typically 1, 2 for larger
* memories, 0 for register type devices with only one
* register)
* data: Where to write the data
* len: How many bytes to read/write
*
* Returns: 0 on success, not 0 on failure
*/
uchar
i2c_write(MV_U8 chanNum, uchar dev_addr, unsigned int offset, int alen, uchar* data, int len)
{
MV_TWSI_SLAVE twsiSlave;
unsigned int i2cFreq = CFG_I2C_SPEED;
DP(puts("i2c_write\n"));
twsiSlave.slaveAddr.type = ADDR7_BIT;
twsiSlave.slaveAddr.address = dev_addr;
if(alen != 0){
twsiSlave.validOffset = MV_TRUE;
twsiSlave.offset = offset;
if(alen == 2)
{
twsiSlave.moreThen256 = MV_TRUE;
}
else
{
twsiSlave.moreThen256 = MV_FALSE;
}
}
i2c_init(chanNum, i2cFreq,0); /* set the i2c frequency */
return mvTwsiWrite (chanNum, &twsiSlave, data, len);
}
/* function to determine if an I2C device is present */
/* chip = device address of chip to check for */
/* */
/* returns 0 = sucessful, the device exists */
/* anything other than zero is failure, no device */
int i2c_probe (MV_U8 chanNum, uchar chip)
{
/* We are just looking for an <ACK> back. */
/* To see if the device/chip is there */
MV_TWSI_ADDR eepromAddress;
unsigned int status = 0;
unsigned int i2cFreq = CFG_I2C_SPEED;
DP(puts("i2c_probe\n"));
i2c_init(chanNum, i2cFreq,0); /* set the i2c frequency */
status = mvTwsiStartBitSet(chanNum);
if (status) {
DP(printf("Transaction start failed: 0x%02x\n", status));
mvTwsiStopBitSet(chanNum);
return (int)status;
}
eepromAddress.type = ADDR7_BIT;
eepromAddress.address = chip;
status = mvTwsiAddrSet(chanNum, &eepromAddress, MV_TWSI_WRITE); /* send the slave address */
if (status) {
DP(printf("Failed to set slave address: 0x%02x\n", status));
mvTwsiStopBitSet(chanNum);
return (int)status;
}
DP(printf("address %#x returned %#x\n",chip,MV_REG_READ(TWSI_STATUS_BAUDE_RATE_REG(chanNum))));
/* issue a stop bit */
mvTwsiStopBitSet(chanNum);
DP(printf("*** successful completion \n"));
return 0; /* successful completion */
}
#endif