text: /*
   * Add by Alan Lu, 07-29-2005
   * For ATMEL AT24C16 EEPROM
   *
   * 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 <i2c.h>
  #ifdef CONFIG_SYS_EEPROM_AT24C16
  #undef DEBUG
  
  void eeprom_init(void)
  {
  #if defined(CONFIG_HARD_I2C) || defined(CONFIG_SOFT_I2C)
  	i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
  #endif
  }
  
  int eeprom_read(unsigned dev_addr, unsigned offset, uchar *buffer,
  			unsigned cnt)
  {
  	int page, count = 0, i = 0;
  	page = offset / 0x100;
  	i = offset % 0x100;
  
  	while (count < cnt) {
  		if (i2c_read(dev_addr|page, i++, 1, buffer+count++, 1) != 0)
  			return 1;
  		if (i > 0xff) {
  			page++;
  			i = 0;
  		}
  	}
  
  	return 0;
  }
  
  /*
   * for CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 2 (16-bit EEPROM address) offset is
   *   0x000nxxxx for EEPROM address selectors at n, offset xxxx in EEPROM.
   *
   * for CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 1 (8-bit EEPROM page address) offset is
   *   0x00000nxx for EEPROM address selectors and page number at n.
   */
  int eeprom_write(unsigned dev_addr, unsigned offset, uchar *buffer,
  			unsigned cnt)
  {
  	int page, i = 0, count = 0;
  
  	page = offset / 0x100;
  	i = offset % 0x100;
  
  	while (count < cnt) {
  		if (i2c_write(dev_addr|page, i++, 1, buffer+count++, 1) != 0)
  			return 1;
  		if (i > 0xff) {
  			page++;
  			i = 0;
  		}
  	}
  
  #if defined(CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS)
  	udelay(CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS * 1000);
  #endif
  
  	return 0;
  }
  
  #ifndef CONFIG_SPI
  int eeprom_probe(unsigned dev_addr, unsigned offset)
  {
  	unsigned char chip;
  
  	/* Probe the chip address */
  #if CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 1 && !defined(CONFIG_SPI_X)
  	chip = offset >> 8; /* block number */
  #else
  	chip = offset >> 16; /* block number */
  #endif /* CONFIG_SYS_I2C_EEPROM_ADDR_LEN, CONFIG_SPI_X */
  
  	chip |= dev_addr; /* insert device address */
  	return (i2c_probe(chip));
  }
  #endif
  #endif
  