xref: /linux/Documentation/devicetree/bindings/eeprom/at25.yaml (revision 8a7c601e14576a22c2bbf7f67455ccf3f3d2737f) 
1# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
2%YAML 1.2
3---
4$id: http://devicetree.org/schemas/eeprom/at25.yaml#
5$schema: http://devicetree.org/meta-schemas/core.yaml#
6
7title: SPI EEPROMs or FRAMs compatible with Atmel's AT25
8
9maintainers:
10  - Christian Eggers <ceggers@arri.de>
11
12properties:
13  $nodename:
14    anyOf:
15      - pattern: "^eeprom@[0-9a-f]{1,2}$"
16      - pattern: "^fram@[0-9a-f]{1,2}$"
17
18  # There are multiple known vendors who manufacture EEPROM chips compatible
19  # with Atmel's AT25. The compatible string requires two items where the
20  # 'vendor' and 'model' parts of the first are the actual chip and the second
21  # item is fixed to "atmel,at25". Some existing bindings only have the
22  # "atmel,at25" part and should be fixed by somebody who knows vendor and
23  # product.
24  compatible:
25    oneOf:
26      - items:
27          - enum:
28              - anvo,anv32e61w
29              - atmel,at25256B
30              - fujitsu,mb85rs1mt
31              - fujitsu,mb85rs256
32              - fujitsu,mb85rs64
33              - microchip,at25160bn
34              - microchip,25lc040
35              - st,m95m02
36              - st,m95256
37              - st,m95640
38              - cypress,fm25
39
40          - const: atmel,at25
41
42      # Please don't use this alternative for new bindings.
43      - items:
44          - const: atmel,at25
45
46  reg:
47    maxItems: 1
48
49  pagesize:
50    $ref: /schemas/types.yaml#/definitions/uint32
51    enum: [1, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192, 16384, 32768, 65536, 131072]
52    description:
53      Size of the eeprom page. FRAMs don't have pages.
54
55  size:
56    $ref: /schemas/types.yaml#/definitions/uint32
57    description:
58      Total eeprom size in bytes.
59      Also used for FRAMs without device ID where the size cannot be detected.
60
61  address-width:
62    $ref: /schemas/types.yaml#/definitions/uint32
63    enum: [ 8, 9, 16, 24 ]
64    description:
65      Number of address bits.
66      For 9 bits, the MSB of the address is sent as bit 3 of the instruction
67      byte, before the address byte.
68
69  spi-cpha: true
70
71  spi-cpol: true
72
73  read-only:
74    description:
75      Disable writes to the eeprom.
76    type: boolean
77
78  wp-gpios:
79    maxItems: 1
80    description:
81      GPIO to which the write-protect pin of the chip is connected.
82
83  # Deprecated: at25,byte-len, at25,addr-mode, at25,page-size
84  at25,byte-len:
85    $ref: /schemas/types.yaml#/definitions/uint32
86    description:
87      Total eeprom size in bytes. Deprecated, use "size" property instead.
88    deprecated: true
89
90  at25,addr-mode:
91    $ref: /schemas/types.yaml#/definitions/uint32
92    description:
93      Addr-mode flags, as defined in include/linux/spi/eeprom.h.
94      Deprecated, use "address-width" property instead.
95    deprecated: true
96
97  at25,page-size:
98    $ref: /schemas/types.yaml#/definitions/uint32
99    description:
100      Size of the eeprom page. Deprecated, use "pagesize" property instead.
101    deprecated: true
102
103required:
104  - compatible
105  - reg
106  - spi-max-frequency
107
108allOf:
109  - $ref: /schemas/spi/spi-peripheral-props.yaml#
110  - $ref: /schemas/nvmem/nvmem.yaml
111  - if:
112      properties:
113        compatible:
114          not:
115            contains:
116              const: cypress,fm25
117    then:
118      required:
119        - pagesize
120        - size
121        - address-width
122
123unevaluatedProperties: false
124
125examples:
126  - |
127    #include <dt-bindings/gpio/gpio.h>
128    spi {
129        #address-cells = <1>;
130        #size-cells = <0>;
131
132        eeprom@0 {
133            compatible = "st,m95256", "atmel,at25";
134            reg = <0>;
135            spi-max-frequency = <5000000>;
136            spi-cpha;
137            spi-cpol;
138            wp-gpios = <&gpio1 3 0>;
139
140            pagesize = <64>;
141            size = <32768>;
142            address-width = <16>;
143        };
144
145        fram@1 {
146            compatible = "cypress,fm25", "atmel,at25";
147            reg = <1>;
148            spi-max-frequency = <40000000>;
149        };
150
151        fram@2 {
152            compatible = "cypress,fm25", "atmel,at25";
153            reg = <2>;
154            spi-max-frequency = <20000000>;
155            size = <2048>;
156        };
157    };
158