root/include/linux/i2c/at24.h

#ifndef _LINUX_AT24_H
#define _LINUX_AT24_H

#include <linux/types.h>

/*
 * As seen through Linux I2C, differences between the most common types of I2C
 * memory include:
 * - How much memory is available (usually specified in bit)?
 * - What write page size does it support?
 * - Special flags (16 bit addresses, read_only, world readable...)?
 *
 * If you set up a custom eeprom type, please double-check the parameters.
 * Especially page_size needs extra care, as you risk data loss if your value
 * is bigger than what the chip actually supports!
 */

struct at24_platform_data {
        u32             byte_len;               /* size (sum of all addr) */
        u16             page_size;              /* for writes */
        u8              flags;
#define AT24_FLAG_ADDR16        0x80    /* address pointer is 16 bit */
#define AT24_FLAG_READONLY      0x40    /* sysfs-entry will be read-only */
#define AT24_FLAG_IRUGO         0x20    /* sysfs-entry will be world-readable */
#define AT24_FLAG_TAKE8ADDR     0x10    /* take always 8 addresses (24c00) */
};

#endif /* _LINUX_AT24_H */