1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
|
# SPDX-License-Identifier: GPL-2.0
%YAML 1.2
---
$id: http://devicetree.org/schemas/mfd/syscon-common.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#
title: System Controller Registers R/W Common Properties
description:
System controller node represents a register region containing a set
of miscellaneous registers. The registers are not cohesive enough to
represent as any specific type of device. The typical use-case is
for some other node's driver, or platform-specific code, to acquire
a reference to the syscon node (e.g. by phandle, node path, or
search using a specific compatible value), interrogate the node (or
associated OS driver) to determine the location of the registers,
and access the registers directly.
maintainers:
- Lee Jones <lee@kernel.org>
select:
properties:
compatible:
contains:
const: syscon
required:
- compatible
properties:
compatible:
contains:
const: syscon
# Always require a specific compatible for syscon
minItems: 2
maxItems: 5 # Should be enough
reg-io-width:
description:
The size (in bytes) of the IO accesses that should be performed
on the device.
enum: [1, 2, 4, 8]
required:
- compatible
- reg
allOf:
- if:
properties:
compatible:
contains:
const: simple-mfd
then:
# Always require a specific compatible for syscon with simple-mfd
properties:
compatible:
minItems: 3
maxItems: 5
- if:
properties:
compatible:
contains:
const: simple-bus
then:
# simple-bus conflicts with syscon - if a device is a system controller
# with miscellaneous registers, then it has at least one dedicated
# function thus it is not a simple bus. Allow existing exceptions.
if:
properties:
compatible:
not:
contains:
# This list CANNOT grow
enum:
- cznic,turris1x-cpld
- img,pistachio-cr-periph
- ti,am3352-scm-conf
- ti,am4372-scm-conf
- ti,dm814-scm-conf
- ti,dm8168-scm-conf
- ti,dra7-scm-conf
- ti,omap2-scm-conf
- ti,omap3-scm-conf
- ti,omap4-sysc-padconf-global
- ti,omap5-scm-wkup-conf
- ti,omap5-sysc-padconf-global
then:
required:
- incorrect-usage-of-simple-bus-and-syscon
additionalProperties: true
examples:
- |
syscon: syscon@1c00000 {
compatible = "allwinner,sun8i-h3-system-controller", "syscon";
reg = <0x01c00000 0x1000>;
};
...
|
