1/* 2 * at24.h - platform_data for the at24 (generic eeprom) driver 3 * (C) Copyright 2008 by Pengutronix 4 * (C) Copyright 2012 by Wolfram Sang 5 * same license as the driver 6 */ 7 8#ifndef _LINUX_AT24_H 9#define _LINUX_AT24_H 10 11#include <linux/types.h> 12#include <linux/memory.h> 13 14/** 15 * struct at24_platform_data - data to set up at24 (generic eeprom) driver 16 * @byte_len: size of eeprom in byte 17 * @page_size: number of byte which can be written in one go 18 * @flags: tunable options, check AT24_FLAG_* defines 19 * @setup: an optional callback invoked after eeprom is probed; enables kernel 20 code to access eeprom via memory_accessor, see example 21 * @context: optional parameter passed to setup() 22 * 23 * If you set up a custom eeprom type, please double-check the parameters. 24 * Especially page_size needs extra care, as you risk data loss if your value 25 * is bigger than what the chip actually supports! 26 * 27 * An example in pseudo code for a setup() callback: 28 * 29 * void get_mac_addr(struct memory_accessor *mem_acc, void *context) 30 * { 31 * u8 *mac_addr = ethernet_pdata->mac_addr; 32 * off_t offset = context; 33 * 34 * // Read MAC addr from EEPROM 35 * if (mem_acc->read(mem_acc, mac_addr, offset, ETH_ALEN) == ETH_ALEN) 36 * pr_info("Read MAC addr from EEPROM: %pM\n", mac_addr); 37 * } 38 * 39 * This function pointer and context can now be set up in at24_platform_data. 40 */ 41 42struct at24_platform_data { 43 u32 byte_len; /* size (sum of all addr) */ 44 u16 page_size; /* for writes */ 45 u8 flags; 46#define AT24_FLAG_ADDR16 0x80 /* address pointer is 16 bit */ 47#define AT24_FLAG_READONLY 0x40 /* sysfs-entry will be read-only */ 48#define AT24_FLAG_IRUGO 0x20 /* sysfs-entry will be world-readable */ 49#define AT24_FLAG_TAKE8ADDR 0x10 /* take always 8 addresses (24c00) */ 50 51 void (*setup)(struct memory_accessor *, void *context); 52 void *context; 53}; 54 55#endif /* _LINUX_AT24_H */ 56