| # SPDX-License-Identifier: GPL-2.0-only |
| %YAML 1.2 |
| --- |
| $id: http://devicetree.org/schemas/powerpc/sleep.yaml# |
| $schema: http://devicetree.org/meta-schemas/core.yaml# |
| |
| title: PowerPC sleep property |
| |
| maintainers: |
| - Rob Herring <robh@kernel.org> |
| |
| description: | |
| Devices on SOCs often have mechanisms for placing devices into low-power |
| states that are decoupled from the devices' own register blocks. Sometimes, |
| this information is more complicated than a cell-index property can |
| reasonably describe. Thus, each device controlled in such a manner |
| may contain a "sleep" property which describes these connections. |
| |
| The sleep property consists of one or more sleep resources, each of |
| which consists of a phandle to a sleep controller, followed by a |
| controller-specific sleep specifier of zero or more cells. |
| |
| The semantics of what type of low power modes are possible are defined |
| by the sleep controller. Some examples of the types of low power modes |
| that may be supported are: |
| |
| - Dynamic: The device may be disabled or enabled at any time. |
| - System Suspend: The device may request to be disabled or remain |
| awake during system suspend, but will not be disabled until then. |
| - Permanent: The device is disabled permanently (until the next hard |
| reset). |
| |
| Some devices may share a clock domain with each other, such that they should |
| only be suspended when none of the devices are in use. Where reasonable, |
| such nodes should be placed on a virtual bus, where the bus has the sleep |
| property. If the clock domain is shared among devices that cannot be |
| reasonably grouped in this manner, then create a virtual sleep controller |
| (similar to an interrupt nexus, except that defining a standardized |
| sleep-map should wait until its necessity is demonstrated). |
| |
| select: true |
| |
| properties: |
| sleep: |
| $ref: /schemas/types.yaml#definitions/phandle-array |
| |
| additionalProperties: true |