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
  29 void 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
  36 int 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  */
  62 int 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
  87 int 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