LXR uboot/board/m501sk/eeprom.c

   1/*
   2 * Add by Alan Lu, 07-29-2005
   3 * For ATMEL AT24C16 EEPROM
   4 *
   5 * See file CREDITS for list of people who contributed to this
   6 * project.
   7 *
   8 * This program is free software; you can redistribute it and/or
   9 * modify it under the terms of the GNU General Public License as
  10 * published by the Free Software Foundation; either version 2 of
  11 * the License, or (at your option) any later version.
  12 *
  13 * This program is distributed in the hope that it will be useful,
  14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 * GNU General Public License for more details.
  17 *
  18 * You should have received a copy of the GNU General Public License
  19 * along with this program; if not, write to the Free Software
  20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  21 * MA 02111-1307 USA
  22 */
  23
  24#include <common.h>
  25#include <i2c.h>
  26#ifdef CONFIG_SYS_EEPROM_AT24C16
  27#undef DEBUG
  28
  29void eeprom_init(void)
  30{
  31#if defined(CONFIG_HARD_I2C) || defined(CONFIG_SOFT_I2C)
  32        i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
  33#endif
  34}
  35
  36int eeprom_read(unsigned dev_addr, unsigned offset, uchar *buffer,
  37                        unsigned cnt)
  38{
  39        int page, count = 0, i = 0;
  40        page = offset / 0x100;
  41        i = offset % 0x100;
  42
  43        while (count < cnt) {
  44                if (i2c_read(dev_addr|page, i++, 1, buffer+count++, 1) != 0)
  45                        return 1;
  46                if (i > 0xff) {
  47                        page++;
  48                        i = 0;
  49                }
  50        }
  51
  52        return 0;
  53}
  54
  55/*
  56 * for CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 2 (16-bit EEPROM address) offset is
  57 *   0x000nxxxx for EEPROM address selectors at n, offset xxxx in EEPROM.
  58 *
  59 * for CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 1 (8-bit EEPROM page address) offset is
  60 *   0x00000nxx for EEPROM address selectors and page number at n.
  61 */
  62int eeprom_write(unsigned dev_addr, unsigned offset, uchar *buffer,
  63                        unsigned cnt)
  64{
  65        int page, i = 0, count = 0;
  66
  67        page = offset / 0x100;
  68        i = offset % 0x100;
  69
  70        while (count < cnt) {
  71                if (i2c_write(dev_addr|page, i++, 1, buffer+count++, 1) != 0)
  72                        return 1;
  73                if (i > 0xff) {
  74                        page++;
  75                        i = 0;
  76                }
  77        }
  78
  79#if defined(CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS)
  80        udelay(CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS * 1000);
  81#endif
  82
  83        return 0;
  84}
  85
  86#ifndef CONFIG_SPI
  87int eeprom_probe(unsigned dev_addr, unsigned offset)
  88{
  89        unsigned char chip;
  90
  91        /* Probe the chip address */
  92#if CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 1 && !defined(CONFIG_SPI_X)
  93        chip = offset >> 8; /* block number */
  94#else
  95        chip = offset >> 16; /* block number */
  96#endif /* CONFIG_SYS_I2C_EEPROM_ADDR_LEN, CONFIG_SPI_X */
  97
  98        chip |= dev_addr; /* insert device address */
  99        return (i2c_probe(chip));
 100}
 101#endif
 102#endif
 103