xref: /freebsd/sys/contrib/device-tree/Bindings/powerpc/sleep.yaml (revision 8ddb146abcdf061be9f2c0db7e391697dafad85c)
1# SPDX-License-Identifier: GPL-2.0-only
2%YAML 1.2
3---
4$id: http://devicetree.org/schemas/powerpc/sleep.yaml#
5$schema: http://devicetree.org/meta-schemas/core.yaml#
6
7title: PowerPC sleep property
8
9maintainers:
10  - Rob Herring <robh@kernel.org>
11
12description: |
13  Devices on SOCs often have mechanisms for placing devices into low-power
14  states that are decoupled from the devices' own register blocks.  Sometimes,
15  this information is more complicated than a cell-index property can
16  reasonably describe.  Thus, each device controlled in such a manner
17  may contain a "sleep" property which describes these connections.
18
19  The sleep property consists of one or more sleep resources, each of
20  which consists of a phandle to a sleep controller, followed by a
21  controller-specific sleep specifier of zero or more cells.
22
23  The semantics of what type of low power modes are possible are defined
24  by the sleep controller.  Some examples of the types of low power modes
25  that may be supported are:
26
27   - Dynamic: The device may be disabled or enabled at any time.
28   - System Suspend: The device may request to be disabled or remain
29     awake during system suspend, but will not be disabled until then.
30   - Permanent: The device is disabled permanently (until the next hard
31     reset).
32
33  Some devices may share a clock domain with each other, such that they should
34  only be suspended when none of the devices are in use.  Where reasonable,
35  such nodes should be placed on a virtual bus, where the bus has the sleep
36  property.  If the clock domain is shared among devices that cannot be
37  reasonably grouped in this manner, then create a virtual sleep controller
38  (similar to an interrupt nexus, except that defining a standardized
39  sleep-map should wait until its necessity is demonstrated).
40
41select: true
42
43properties:
44  sleep:
45    $ref: /schemas/types.yaml#/definitions/phandle-array
46
47additionalProperties: true
48