misc: at24: describe platform_data with kernel_doc

/*

 * 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>

/*

 * 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...)?

/**

 * 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 {