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EEPROMs (I2C)

Required properties:

  - compatible: Must be a "<manufacturer>,<model>" pair. The following <model>
                values are supported (assuming "atmel" as manufacturer):

                "atmel,24c00",
                "atmel,24c01",
                "atmel,24cs01",
                "atmel,24c02",
                "atmel,24cs02",
                "atmel,24mac402",
                "atmel,24mac602",
                "atmel,spd",
                "atmel,24c04",
                "atmel,24cs04",
                "atmel,24c08",
                "atmel,24cs08",
                "atmel,24c16",
                "atmel,24cs16",
                "atmel,24c32",
                "atmel,24cs32",
                "atmel,24c64",
                "atmel,24cs64",
                "atmel,24c128",
                "atmel,24c256",
                "atmel,24c512",
                "atmel,24c1024",
                "atmel,24c2048",

                If <manufacturer> is not "atmel", then a fallback must be used
                with the same <model> and "atmel" as manufacturer.

                Example:
                        compatible = "microchip,24c128", "atmel,24c128";

                Supported manufacturers are:

                "catalyst",
                "microchip",
                "nxp",
                "ramtron",
                "renesas",
                "rohm",
                "st",

                Some vendors use different model names for chips which are just
                variants of the above. Known such exceptions are listed below:

                "nxp,se97b" - the fallback is "atmel,24c02",
                "renesas,r1ex24002" - the fallback is "atmel,24c02"
                "renesas,r1ex24016" - the fallback is "atmel,24c16"
                "renesas,r1ex24128" - the fallback is "atmel,24c128"
                "rohm,br24t01" - the fallback is "atmel,24c01"

  - reg: The I2C address of the EEPROM.

Optional properties:

  - pagesize: The length of the pagesize for writing. Please consult the
              manual of your device, that value varies a lot. A wrong value
              may result in data loss! If not specified, a safety value of
              '1' is used which will be very slow.

  - read-only: This parameterless property disables writes to the eeprom.

  - size: Total eeprom size in bytes.

  - no-read-rollover: This parameterless property indicates that the
                      multi-address eeprom does not automatically roll over
                      reads to the next slave address. Please consult the
                      manual of your device.

  - wp-gpios: GPIO to which the write-protect pin of the chip is connected.

  - address-width: number of address bits (one of 8, 16).

  - num-addresses: total number of i2c slave addresses this device takes

Example:

eeprom@52 {
	compatible = "atmel,24c32";
	reg = <0x52>;
	pagesize = <32>;
	wp-gpios = <&gpio1 3 0>;
	num-addresses = <8>;
};