LXR linux/include/linux/platform

   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/nvmem-consumer.h>
  13#include <linux/bitops.h>
  14
  15/**
  16 * struct at24_platform_data - data to set up at24 (generic eeprom) driver
  17 * @byte_len: size of eeprom in byte
  18 * @page_size: number of byte which can be written in one go
  19 * @flags: tunable options, check AT24_FLAG_* defines
  20 * @setup: an optional callback invoked after eeprom is probed; enables kernel
  21        code to access eeprom via nvmem, see example
  22 * @context: optional parameter passed to setup()
  23 *
  24 * If you set up a custom eeprom type, please double-check the parameters.
  25 * Especially page_size needs extra care, as you risk data loss if your value
  26 * is bigger than what the chip actually supports!
  27 *
  28 * An example in pseudo code for a setup() callback:
  29 *
  30 * void get_mac_addr(struct nvmem_device *nvmem, void *context)
  31 * {
  32 *      u8 *mac_addr = ethernet_pdata->mac_addr;
  33 *      off_t offset = context;
  34 *
  35 *      // Read MAC addr from EEPROM
  36 *      if (nvmem_device_read(nvmem, offset, ETH_ALEN, mac_addr) == ETH_ALEN)
  37 *              pr_info("Read MAC addr from EEPROM: %pM\n", mac_addr);
  38 * }
  39 *
  40 * This function pointer and context can now be set up in at24_platform_data.
  41 */
  42
  43struct at24_platform_data {
  44        u32             byte_len;               /* size (sum of all addr) */
  45        u16             page_size;              /* for writes */
  46        u8              flags;
  47#define AT24_FLAG_ADDR16        BIT(7)  /* address pointer is 16 bit */
  48#define AT24_FLAG_READONLY      BIT(6)  /* sysfs-entry will be read-only */
  49#define AT24_FLAG_IRUGO         BIT(5)  /* sysfs-entry will be world-readable */
  50#define AT24_FLAG_TAKE8ADDR     BIT(4)  /* take always 8 addresses (24c00) */
  51#define AT24_FLAG_SERIAL        BIT(3)  /* factory-programmed serial number */
  52#define AT24_FLAG_MAC           BIT(2)  /* factory-programmed mac address */
  53
  54        void            (*setup)(struct nvmem_device *nvmem, void *context);
  55        void            *context;
  56};
  57
  58#endif /* _LINUX_AT24_H */
  59