linux-stable/include/linux/i2c/at24.h
Kevin Hilman 7274ec8bd7 memory_accessor: implement the new memory_accessor interface for I2C EEPROM
In the case of at24, the platform code registers a 'setup' callback with
the at24_platform_data.  When the at24 driver detects an EEPROM, it fills
out the read and write functions of the memory_accessor and calls the
setup callback passing the memory_accessor struct.  The platform code can
then use the read/write functions in the memory_accessor struct for
reading and writing the EEPROM.

Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-02 19:04:50 -07:00

32 lines
1.1 KiB
C

#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...)?
*
* 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!
*/
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 */