/* * at24.h - platform_data for the at24 (generic eeprom) driver * (C) Copyright 2008 by Pengutronix * (C) Copyright 2012 by Wolfram Sang * same license as the driver */ #ifndef _LINUX_AT24_H #define _LINUX_AT24_H #include <linux/types.h> #include <linux/memory.h> /** * struct at24_platform_data - data to set up at24 (generic eeprom) driver * @byte_len: size of eeprom in byte * @page_size: number of byte which can be written in one go * @flags: tunable options, check AT24_FLAG_* defines * @setup: an optional callback invoked after eeprom is probed; enables kernel code to access eeprom via memory_accessor, see example * @context: optional parameter passed to setup() * * 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! * * An example in pseudo code for a setup() callback: * * void get_mac_addr(struct memory_accessor *mem_acc, void *context) * { * u8 *mac_addr = ethernet_pdata->mac_addr; * off_t offset = context; * * // Read MAC addr from EEPROM * if (mem_acc->read(mem_acc, mac_addr, offset, ETH_ALEN) == ETH_ALEN) * pr_info("Read MAC addr from EEPROM: %pM\n", mac_addr); * } * * This function pointer and context can now be set up in at24_platform_data. */ 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) */ void (*setup)(struct memory_accessor *, void *context); void *context; }; #endif /* _LINUX_AT24_H */