rockbox/firmware/drivers/eeprom_24cxx.c
Bertrik Sikken 8e2ff63a7e Various files: make function implementations consistent with their declaration in the header file or static if
they're local.


git-svn-id: svn://svn.rockbox.org/rockbox/trunk@19892 a1c6a512-1295-4272-9138-f99709370657
2009-01-31 23:51:11 +00:00

159 lines
3.7 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2006 by Miika Pekkarinen
*
* 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 software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include "logf.h"
#include "string.h"
#include "inttypes.h"
#include "sw_i2c.h"
#include "eeprom_24cxx.h"
/* Use cache to speedup writing to the chip. */
static char data_cache[EEPROM_SIZE];
static uint8_t cached_bitfield[EEPROM_SIZE/8];
#define IS_CACHED(addr) (cached_bitfield[addr/8] & (1 << (addr % 8)))
#define SET_CACHED(addr) (cached_bitfield[addr/8] |= 1 << (addr % 8))
void eeprom_24cxx_init(void)
{
sw_i2c_init();
memset(cached_bitfield, 0, sizeof cached_bitfield);
}
static int eeprom_24cxx_read_byte(unsigned int address, char *c)
{
int ret;
char byte;
int count = 0;
if (address >= EEPROM_SIZE)
{
logf("EEPROM address: %d", address);
return -9;
}
/* Check from cache. */
if (IS_CACHED(address))
{
logf("EEPROM RCached: %d", address);
*c = data_cache[address];
return 0;
}
*c = 0;
do
{
ret = sw_i2c_read(EEPROM_ADDR, address, &byte, 1);
} while (ret < 0 && count++ < 200);
if (ret < 0)
{
logf("EEPROM RFail: %d/%d/%d", ret, address, count);
return ret;
}
if (count)
{
/* keep between {} as logf is whitespace in normal builds */
logf("EEPROM rOK: %d retries", count);
}
/* Cache the byte. */
data_cache[address] = byte;
SET_CACHED(address);
*c = byte;
return 0;
}
static int eeprom_24cxx_write_byte(unsigned int address, char c)
{
int ret;
int count = 0;
if (address >= EEPROM_SIZE)
{
logf("EEPROM address: %d", address);
return -9;
}
/* Check from cache. */
if (IS_CACHED(address) && data_cache[address] == c)
{
logf("EEPROM WCached: %d", address);
return 0;
}
do
{
ret = sw_i2c_write(EEPROM_ADDR, address, &c, 1);
} while (ret < 0 && count++ < 200) ;
if (ret < 0)
{
logf("EEPROM WFail: %d/%d", ret, address);
return ret;
}
if (count)
{
/* keep between {} as logf is whitespace in normal builds */
logf("EEPROM wOK: %d retries", count);
}
SET_CACHED(address);
data_cache[address] = c;
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 i;
for (i = 0; i < length; i++)
{
if (eeprom_24cxx_write_byte(address+i, buf[i]) < 0)
return -1;
}
return 0;
}