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/*
* (C) Copyright 2004
* DAVE Srl
* http://www.dave-tech.it
* http://www.wawnet.biz
* mailto:info@wawnet.biz
*
* See file CREDITS for list of people who contributed to this
* project.
*
* This program 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.
*
* This program 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 this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#include <common.h>
#include <command.h>
#include <asm/hardware.h>
/*
* Initialization, must be called once on start up, may be called
* repeatedly to change the speed and slave addresses.
*/
void i2c_init(int speed, int slaveaddr)
{
/*
setting up I2C support
*/
unsigned int save_F,save_PF,rIICCON,rPCONA,rPDATA,rPCONF,rPUPF;
save_F = PCONF;
save_PF = PUPF;
rPCONF = ((save_F & ~(0xF))| 0xa);
rPUPF = (save_PF | 0x3);
PCONF = rPCONF; /*PF0:IICSCL, PF1:IICSDA*/
PUPF = rPUPF; /* Disable pull-up */
/* Configuring pin for WC pin of EEprom */
rPCONA = PCONA;
rPCONA &= ~(1<<9);
PCONA = rPCONA;
rPDATA = PDATA;
rPDATA &= ~(1<<9);
PDATA = rPDATA;
/*
Enable ACK, IICCLK=MCLK/16, enable interrupt
75MHz/16/(12+1) = 390625 Hz
*/
rIICCON=(1<<7)|(0<<6)|(1<<5)|(0xC);
IICCON = rIICCON;
IICADD = slaveaddr;
}
/*
* Probe the given I2C chip address. Returns 0 if a chip responded,
* not 0 on failure.
*/
int i2c_probe(uchar chip)
{
/*
not implemented
*/
printf("i2c_probe chip %d\n", (int) chip);
return -1;
}
/*
* Read/Write interface:
* chip: I2C chip address, range 0..127
* addr: 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)
* buffer: Where to read/write the data
* len: How many bytes to read/write
*
* Returns: 0 on success, not 0 on failure
*/
#define S3C44B0X_rIIC_INTPEND (1<<4)
#define S3C44B0X_rIIC_LAST_RECEIV_BIT (1<<0)
#define S3C44B0X_rIIC_INTERRUPT_ENABLE (1<<5)
#define S3C44B0_IIC_TIMEOUT 100
int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len)
{
int k, j, temp;
u32 rIICSTAT;
/*
send the device offset
*/
rIICSTAT = 0xD0;
IICSTAT = rIICSTAT;
IICDS = chip; /* this is a write operation... */
rIICSTAT |= (1<<5);
IICSTAT = rIICSTAT;
for(k=0; k<S3C44B0_IIC_TIMEOUT; k++) {
temp = IICCON;
if( (temp & S3C44B0X_rIIC_INTPEND) == S3C44B0X_rIIC_INTPEND)
break;
udelay(2000);
}
if (k==S3C44B0_IIC_TIMEOUT)
return -1;
/* wait and check ACK */
temp = IICSTAT;
if ((temp & S3C44B0X_rIIC_LAST_RECEIV_BIT) == S3C44B0X_rIIC_LAST_RECEIV_BIT )
return -1;
IICDS = addr;
IICCON = IICCON & ~(S3C44B0X_rIIC_INTPEND);
/* wait and check ACK */
for(k=0; k<S3C44B0_IIC_TIMEOUT; k++) {
temp = IICCON;
if( (temp & S3C44B0X_rIIC_INTPEND) == S3C44B0X_rIIC_INTPEND)
break;
udelay(2000);
}
if (k==S3C44B0_IIC_TIMEOUT)
return -1;
temp = IICSTAT;
if ((temp & S3C44B0X_rIIC_LAST_RECEIV_BIT) == S3C44B0X_rIIC_LAST_RECEIV_BIT )
return -1;
/*
now we can start with the read operation...
*/
IICDS = chip | 0x01; /* this is a read operation... */
rIICSTAT = 0x90; /*master recv*/
rIICSTAT |= (1<<5);
IICSTAT = rIICSTAT;
IICCON = IICCON & ~(S3C44B0X_rIIC_INTPEND);
/* wait and check ACK */
for(k=0; k<S3C44B0_IIC_TIMEOUT; k++) {
temp = IICCON;
if( (temp & S3C44B0X_rIIC_INTPEND) == S3C44B0X_rIIC_INTPEND)
break;
udelay(2000);
}
if (k==S3C44B0_IIC_TIMEOUT)
return -1;
temp = IICSTAT;
if ((temp & S3C44B0X_rIIC_LAST_RECEIV_BIT) == S3C44B0X_rIIC_LAST_RECEIV_BIT )
return -1;
for (j=0; j<len-1; j++) {
/*clear pending bit to resume */
temp = IICCON & ~(S3C44B0X_rIIC_INTPEND);
IICCON = temp;
/* wait and check ACK */
for(k=0; k<S3C44B0_IIC_TIMEOUT; k++) {
temp = IICCON;
if( (temp & S3C44B0X_rIIC_INTPEND) == S3C44B0X_rIIC_INTPEND)
break;
udelay(2000);
}
if (k==S3C44B0_IIC_TIMEOUT)
return -1;
buffer[j] = IICDS; /*save readed data*/
} /*end for(j)*/
/*
reading the last data
unset ACK generation
*/
temp = IICCON & ~(S3C44B0X_rIIC_INTPEND | (1<<7));
IICCON = temp;
/* wait but NOT check ACK */
for(k=0; k<S3C44B0_IIC_TIMEOUT; k++) {
temp = IICCON;
if( (temp & S3C44B0X_rIIC_INTPEND) == S3C44B0X_rIIC_INTPEND)
break;
udelay(2000);
}
if (k==S3C44B0_IIC_TIMEOUT)
return -1;
buffer[j] = IICDS; /*save readed data*/
rIICSTAT = 0x90; /*master recv*/
/* Write operation Terminate sending STOP */
IICSTAT = rIICSTAT;
/*Clear Int Pending Bit to RESUME*/
temp = IICCON;
IICCON = temp & (~S3C44B0X_rIIC_INTPEND);
IICCON = IICCON | (1<<7); /*restore ACK generation*/
return 0;
}
int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len)
{
int j, k;
u32 rIICSTAT, temp;
/*
send the device offset
*/
rIICSTAT = 0xD0;
IICSTAT = rIICSTAT;
IICDS = chip; /* this is a write operation... */
rIICSTAT |= (1<<5);
IICSTAT = rIICSTAT;
IICCON = IICCON & ~(S3C44B0X_rIIC_INTPEND);
/* wait and check ACK */
for(k=0; k<S3C44B0_IIC_TIMEOUT; k++) {
temp = IICCON;
if( (temp & S3C44B0X_rIIC_INTPEND) == S3C44B0X_rIIC_INTPEND)
break;
udelay(2000);
}
if (k==S3C44B0_IIC_TIMEOUT)
return -1;
temp = IICSTAT;
if ((temp & S3C44B0X_rIIC_LAST_RECEIV_BIT) == S3C44B0X_rIIC_LAST_RECEIV_BIT )
return -1;
IICDS = addr;
IICCON = IICCON & ~(S3C44B0X_rIIC_INTPEND);
/* wait and check ACK */
for(k=0; k<S3C44B0_IIC_TIMEOUT; k++) {
temp = IICCON;
if( (temp & S3C44B0X_rIIC_INTPEND) == S3C44B0X_rIIC_INTPEND)
break;
udelay(2000);
}
if (k==S3C44B0_IIC_TIMEOUT)
return -1;
temp = IICSTAT;
if ((temp & S3C44B0X_rIIC_LAST_RECEIV_BIT) == S3C44B0X_rIIC_LAST_RECEIV_BIT )
return -1;
/*
now we can start with the read write operation
*/
for (j=0; j<len; j++) {
IICDS = buffer[j]; /*prerare data to write*/
/*clear pending bit to resume*/
temp = IICCON & ~(S3C44B0X_rIIC_INTPEND);
IICCON = temp;
/* wait but NOT check ACK */
for(k=0; k<S3C44B0_IIC_TIMEOUT; k++) {
temp = IICCON;
if( (temp & S3C44B0X_rIIC_INTPEND) == S3C44B0X_rIIC_INTPEND)
break;
udelay(2000);
}
if (k==S3C44B0_IIC_TIMEOUT)
return -1;
} /* end for(j) */
/* sending stop to terminate */
rIICSTAT = 0xD0; /*master send*/
IICSTAT = rIICSTAT;
/*Clear Int Pending Bit to RESUME*/
temp = IICCON;
IICCON = temp & (~S3C44B0X_rIIC_INTPEND);
return 0;
}
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