xref: /linux/Documentation/devicetree/bindings/mfd/syscon.yaml (revision 48dea9a700c8728cc31a1dd44588b97578de86ee) 
1# SPDX-License-Identifier: GPL-2.0
2%YAML 1.2
3---
4$id: http://devicetree.org/schemas/mfd/syscon.yaml#
5$schema: http://devicetree.org/meta-schemas/core.yaml#
6
7title: System Controller Registers R/W Device Tree Bindings
8
9description: |
10  System controller node represents a register region containing a set
11  of miscellaneous registers. The registers are not cohesive enough to
12  represent as any specific type of device. The typical use-case is
13  for some other node's driver, or platform-specific code, to acquire
14  a reference to the syscon node (e.g. by phandle, node path, or
15  search using a specific compatible value), interrogate the node (or
16  associated OS driver) to determine the location of the registers,
17  and access the registers directly.
18
19maintainers:
20  - Lee Jones <lee.jones@linaro.org>
21
22select:
23  properties:
24    compatible:
25      contains:
26        enum:
27          - syscon
28
29  required:
30    - compatible
31
32properties:
33  compatible:
34    anyOf:
35      - items:
36          - enum:
37              - allwinner,sun8i-a83t-system-controller
38              - allwinner,sun8i-h3-system-controller
39              - allwinner,sun8i-v3s-system-controller
40              - allwinner,sun50i-a64-system-controller
41              - microchip,sparx5-cpu-syscon
42              - mstar,msc313-pmsleep
43
44          - const: syscon
45
46      - contains:
47          const: syscon
48        minItems: 2
49        maxItems: 4  # Should be enough
50
51  reg:
52    maxItems: 1
53
54  reg-io-width:
55    description: |
56      The size (in bytes) of the IO accesses that should be performed
57      on the device.
58    $ref: /schemas/types.yaml#/definitions/uint32
59    enum: [1, 2, 4, 8]
60
61  hwlocks:
62    maxItems: 1
63    description:
64      Reference to a phandle of a hardware spinlock provider node.
65
66required:
67  - compatible
68  - reg
69
70unevaluatedProperties: false
71
72examples:
73  - |
74    syscon: syscon@1c00000 {
75        compatible = "allwinner,sun8i-h3-system-controller", "syscon";
76        reg = <0x01c00000 0x1000>;
77    };
78
79  - |
80    gpr: iomuxc-gpr@20e0000 {
81        compatible = "fsl,imx6q-iomuxc-gpr", "syscon";
82        reg = <0x020e0000 0x38>;
83        hwlocks = <&hwlock1 1>;
84    };
85
86...
87