diff options
Diffstat (limited to 'include/linux/i2c')
-rw-r--r-- | include/linux/i2c/at24.h | 35 |
1 files changed, 29 insertions, 6 deletions
diff --git a/include/linux/i2c/at24.h b/include/linux/i2c/at24.h index 8ace93024d60..285025a9cdc9 100644 --- a/include/linux/i2c/at24.h +++ b/include/linux/i2c/at24.h @@ -1,19 +1,42 @@ +/* + * 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 { |