linux-stable/include/linux/platform_data/at24.h
Bartosz Golaszewski 0b813658c1 eeprom: at24: add support for at24mac series
Add a new read function to the at24 driver allowing to retrieve the
factory-programmed mac address embedded in chips from the at24mac
family.

These chips can be instantiated similarily to the at24cs family,
except that there's no way of having access to both the serial number
and the mac address at the same time - the user must instantiate
either an at24cs or at24mac device as both special memory areas are
accessible on the same slave address.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-07-17 19:58:00 +02:00

58 lines
2 KiB
C

/*
* 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/nvmem-consumer.h>
#include <linux/bitops.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 nvmem, 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 nvmem_device *nvmem, void *context)
* {
* u8 *mac_addr = ethernet_pdata->mac_addr;
* off_t offset = context;
*
* // Read MAC addr from EEPROM
* if (nvmem_device_read(nvmem, offset, ETH_ALEN, mac_addr) == 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 BIT(7) /* address pointer is 16 bit */
#define AT24_FLAG_READONLY BIT(6) /* sysfs-entry will be read-only */
#define AT24_FLAG_IRUGO BIT(5) /* sysfs-entry will be world-readable */
#define AT24_FLAG_TAKE8ADDR BIT(4) /* take always 8 addresses (24c00) */
#define AT24_FLAG_SERIAL BIT(3) /* factory-programmed serial number */
#define AT24_FLAG_MAC BIT(2) /* factory-programmed mac address */
void (*setup)(struct nvmem_device *nvmem, void *context);
void *context;
};
#endif /* _LINUX_AT24_H */