rockbox/firmware/drivers/eeprom_24cxx.c
2006-08-07 22:30:12 +00:00

389 lines
7.5 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2006 by Miika Pekkarinen
*
* All files in this archive are subject to the GNU General Public License.
* See the file COPYING in the source tree root for full license agreement.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include "lcd.h"
#include "cpu.h"
#include "system.h"
#include "kernel.h"
#include "thread.h"
#include "debug.h"
#include "logf.h"
#include "sprintf.h"
#include "string.h"
#include "eeprom_24cxx.h"
/**
* I2C-functions are copied and ported from fmradio.c.
*/
#define SW_I2C_WRITE 0
#define SW_I2C_READ 1
/* cute little functions, atomic read-modify-write */
/* SCL is GPIO, 12 */
#define SCL_LO and_l(~0x00001000, &GPIO_OUT) // and_b(~0x10, &PBDRL)
#define SCL_HI or_l( 0x00001000, &GPIO_OUT) // or_b( 0x10, &PBDRL)
#define SCL_INPUT and_l(~0x00001000, &GPIO_ENABLE) // and_b(~0x10, &PBIORL)
#define SCL_OUTPUT or_l( 0x00001000, &GPIO_ENABLE) // or_b( 0x10, &PBIORL)
#define SCL ( 0x00001000 & GPIO_READ) // (PBDR & 0x0010)
/* SDA is GPIO1, 13 */
#define SDA_LO and_l(~0x00002000, &GPIO1_OUT) // and_b(~0x02, &PBDRL)
#define SDA_HI or_l( 0x00002000, &GPIO1_OUT) // or_b( 0x02, &PBDRL)
#define SDA_INPUT and_l(~0x00002000, &GPIO1_ENABLE) // and_b(~0x02, &PBIORL)
#define SDA_OUTPUT or_l( 0x00002000, &GPIO1_ENABLE) // or_b( 0x02, &PBIORL)
#define SDA ( 0x00002000 & GPIO1_READ) // (PBDR & 0x0002)
/* delay loop to achieve 400kHz at 120MHz CPU frequency */
#define DELAY do { int _x; for(_x=0;_x<22;_x++);} while(0)
static void sw_i2c_init(void)
{
logf("sw_i2c_init");
or_l(0x00001000, &GPIO_FUNCTION);
or_l(0x00002000, &GPIO1_FUNCTION);
SDA_HI;
SCL_HI;
SDA_OUTPUT;
SCL_OUTPUT;
}
static void sw_i2c_start(void)
{
SCL_LO;
SCL_OUTPUT;
DELAY;
SDA_HI;
SDA_OUTPUT;
DELAY;
SCL_HI;
DELAY;
SDA_LO;
DELAY;
SCL_LO;
}
static void sw_i2c_stop(void)
{
// SCL_LO;
// DELAY;
// SDA_LO;
// DELAY;
SCL_HI;
DELAY;
SDA_HI;
DELAY;
}
static void sw_i2c_ack(void)
{
SCL_LO;
SDA_LO;
DELAY;
SCL_HI;
DELAY;
}
static bool sw_i2c_getack(void)
{
bool ret = true;
int count = 10;
SCL_LO;
SDA_INPUT; /* And set to input */
DELAY;
SCL_HI;
DELAY;
while (SDA && count--)
DELAY;
if (SDA)
/* ack failed */
ret = false;
SCL_LO;
SCL_OUTPUT;
DELAY;
SDA_LO;
SDA_OUTPUT;
return ret;
}
static void sw_i2c_outb(unsigned char byte)
{
int i;
/* clock out each bit, MSB first */
for ( i=0x80; i; i>>=1 )
{
SCL_LO;
DELAY;
if ( i & byte )
SDA_HI;
else
SDA_LO;
DELAY;
SCL_HI;
DELAY;
}
// SDA_LO;
}
static unsigned char sw_i2c_inb(void)
{
int i;
unsigned char byte = 0;
SDA_INPUT; /* And set to input */
/* clock in each bit, MSB first */
for ( i=0x80; i; i>>=1 )
{
SCL_HI;
DELAY;
if ( SDA )
byte |= i;
SCL_LO;
DELAY;
}
SDA_OUTPUT;
sw_i2c_ack();
return byte;
}
int sw_i2c_write(int location, const unsigned char* buf, int count)
{
int i;
sw_i2c_start();
sw_i2c_outb((EEPROM_ADDR & 0xfe) | SW_I2C_WRITE);
if (!sw_i2c_getack())
{
sw_i2c_stop();
return -1;
}
sw_i2c_outb(location);
if (!sw_i2c_getack())
{
sw_i2c_stop();
return -2;
}
for (i=0; i<count; i++)
{
sw_i2c_outb(buf[i]);
if (!sw_i2c_getack())
{
sw_i2c_stop();
return -3;
}
}
sw_i2c_stop();
return 0;
}
int sw_i2c_write_byte(int location, unsigned char byte)
{
sw_i2c_start();
sw_i2c_outb((EEPROM_ADDR & 0xfe) | SW_I2C_WRITE);
if (!sw_i2c_getack())
{
sw_i2c_stop();
return -1;
}
sw_i2c_outb(location);
if (!sw_i2c_getack())
{
sw_i2c_stop();
return -2;
}
sw_i2c_outb(byte);
if (!sw_i2c_getack())
{
sw_i2c_stop();
return -3;
}
sw_i2c_stop();
return 0;
}
int sw_i2c_read(unsigned char location, unsigned char* byte)
{
sw_i2c_start();
sw_i2c_outb((EEPROM_ADDR & 0xfe) | SW_I2C_WRITE);
if (!sw_i2c_getack())
{
sw_i2c_stop();
return -1;
}
sw_i2c_outb(location);
if (!sw_i2c_getack())
{
sw_i2c_stop();
return -2;
}
sw_i2c_start();
sw_i2c_outb((EEPROM_ADDR & 0xfe) | SW_I2C_READ);
if (!sw_i2c_getack())
{
sw_i2c_stop();
return -3;
}
*byte = sw_i2c_inb();
sw_i2c_stop();
return 0;
}
void eeprom_24cxx_init(void)
{
sw_i2c_init();
}
int eeprom_24cxx_read_byte(unsigned int address, char *c)
{
int ret;
char byte;
int count = 10;
if (address >= EEPROM_SIZE)
{
logf("EEPROM address: %d", address);
return -9;
}
*c = 0;
do
{
ret = sw_i2c_read(address, &byte);
if (ret < 0)
{
/* keep between {} as logf is whitespace in normal builds */
logf("EEPROM Fail: %d/%d", ret, address);
}
} while (ret < 0 && count--);
if (ret < 0)
{
logf("EEPROM RFail: %d/%d", ret, address);
return ret;
}
*c = byte;
return 0;
}
int eeprom_24cxx_write_byte(unsigned int address, char c)
{
int ret;
int count = 100;
if (address >= EEPROM_SIZE)
{
logf("EEPROM address: %d", address);
return -9;
}
do
{
ret = sw_i2c_write_byte(address, c);
if (ret < 0)
{
/* keep between {} as logf is whitespace in normal builds */
logf("EEPROM Fail: %d/%d", ret, address);
}
} while (ret < 0 && count--) ;
if (ret < 0)
{
logf("EEPROM WFail: %d/%d", ret, address);
return ret;
}
return 0;
}
int eeprom_24cxx_read(unsigned char address, void *dest, int length)
{
char *buf = (char *)dest;
int ret = 0;
int i;
for (i = 0; i < length; i++)
{
ret = eeprom_24cxx_read_byte(address+i, &buf[i]);
if (ret < 0)
return ret;
}
return ret;
}
int eeprom_24cxx_write(unsigned char address, const void *src, int length)
{
const char *buf = (const char *)src;
int count = 10;
int i;
bool ok;
while (count-- > 0)
{
for (i = 0; i < length; i++)
eeprom_24cxx_write_byte(address+i, buf[i]);
ok = true;
for (i = 0; i < length; i++)
{
char byte;
eeprom_24cxx_read_byte(address+i, &byte);
if (byte != buf[i])
{
logf("Verify failed: %d/%d", address+i, count);
ok = false;
break;
}
}
if (ok)
return 0;
}
return -1;
}