xref: /linux/Documentation/devicetree/bindings/mfd/syscon.yaml (revision 891adc1303fe482cd683d8a3054040577484051a) 
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              - hisilicon,dsa-subctrl
42              - hisilicon,hi6220-sramctrl
43              - hisilicon,pcie-sas-subctrl
44              - hisilicon,peri-subctrl
45              - microchip,sparx5-cpu-syscon
46              - mstar,msc313-pmsleep
47
48          - const: syscon
49
50      - contains:
51          const: syscon
52        minItems: 2
53        maxItems: 4  # Should be enough
54
55  reg:
56    maxItems: 1
57
58  reg-io-width:
59    description: |
60      The size (in bytes) of the IO accesses that should be performed
61      on the device.
62    $ref: /schemas/types.yaml#/definitions/uint32
63    enum: [1, 2, 4, 8]
64
65  hwlocks:
66    maxItems: 1
67    description:
68      Reference to a phandle of a hardware spinlock provider node.
69
70required:
71  - compatible
72  - reg
73
74unevaluatedProperties: false
75
76examples:
77  - |
78    syscon: syscon@1c00000 {
79        compatible = "allwinner,sun8i-h3-system-controller", "syscon";
80        reg = <0x01c00000 0x1000>;
81    };
82
83  - |
84    gpr: iomuxc-gpr@20e0000 {
85        compatible = "fsl,imx6q-iomuxc-gpr", "syscon";
86        reg = <0x020e0000 0x38>;
87        hwlocks = <&hwlock1 1>;
88    };
89
90...
91