xref: /freebsd/sys/contrib/device-tree/Bindings/eeprom/at25.txt (revision 43a5ec4eb41567cc92586503212743d89686d78f)
1EEPROMs (SPI) compatible with Atmel at25.
2
3Required properties:
4- compatible : Should be "<vendor>,<type>", and generic value "atmel,at25".
5  Example "<vendor>,<type>" values:
6    "anvo,anv32e61w"
7    "microchip,25lc040"
8    "st,m95m02"
9    "st,m95256"
10
11- reg : chip select number
12- spi-max-frequency : max spi frequency to use
13- pagesize : size of the eeprom page
14- size : total eeprom size in bytes
15- address-width : number of address bits (one of 8, 9, 16, or 24).
16  For 9 bits, the MSB of the address is sent as bit 3 of the instruction
17  byte, before the address byte.
18
19Optional properties:
20- spi-cpha : SPI shifted clock phase, as per spi-bus bindings.
21- spi-cpol : SPI inverse clock polarity, as per spi-bus bindings.
22- read-only : this parameter-less property disables writes to the eeprom
23- wp-gpios : GPIO to which the write-protect pin of the chip is connected
24
25Obsolete legacy properties can be used in place of "size", "pagesize",
26"address-width", and "read-only":
27- at25,byte-len : total eeprom size in bytes
28- at25,addr-mode : addr-mode flags, as defined in include/linux/spi/eeprom.h
29- at25,page-size : size of the eeprom page
30
31Additional compatible properties are also allowed.
32
33Example:
34	eeprom@0 {
35		compatible = "st,m95256", "atmel,at25";
36		reg = <0>
37		spi-max-frequency = <5000000>;
38		spi-cpha;
39		spi-cpol;
40		wp-gpios = <&gpio1 3 0>;
41
42		pagesize = <64>;
43		size = <32768>;
44		address-width = <16>;
45	};
46