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authorMark Brown <broonie@kernel.org>2014-12-13 11:39:36 +0000
committerMark Brown <broonie@kernel.org>2014-12-13 11:39:36 +0000
commit3e5fe00cd38e033796a0de2ea9928c0cb460e6b6 (patch)
tree0996fa20df211dd113519735846c8555d74d3d03 /Documentation
parent32a13f39f539963aee2c0b08f4da973db192a2ff (diff)
parent6920cae74d18abc2e1a2fda0970f8e9889ef3b7d (diff)
Merge remote-tracking branch 'lsk/v3.10/topic/genpd' into linux-linaro-lsklsk-v3.10-14.12
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diff --git a/Documentation/devicetree/bindings/power/power_domain.txt b/Documentation/devicetree/bindings/power/power_domain.txt
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+* Generic PM domains
+System on chip designs are often divided into multiple PM domains that can be
+used for power gating of selected IP blocks for power saving by reduced leakage
+This device tree binding can be used to bind PM domain consumer devices with
+their PM domains provided by PM domain providers. A PM domain provider can be
+represented by any node in the device tree and can provide one or more PM
+domains. A consumer node can refer to the provider by a phandle and a set of
+phandle arguments (so called PM domain specifiers) of length specified by the
+#power-domain-cells property in the PM domain provider node.
+==PM domain providers==
+Required properties:
+ - #power-domain-cells : Number of cells in a PM domain specifier;
+ Typically 0 for nodes representing a single PM domain and 1 for nodes
+ providing multiple PM domains (e.g. power controllers), but can be any value
+ as specified by device tree binding documentation of particular provider.
+ power: power-controller@12340000 {
+ compatible = "foo,power-controller";
+ reg = <0x12340000 0x1000>;
+ #power-domain-cells = <1>;
+ };
+The node above defines a power controller that is a PM domain provider and
+expects one cell as its phandle argument.
+==PM domain consumers==
+Required properties:
+ - power-domains : A phandle and PM domain specifier as defined by bindings of
+ the power controller specified by phandle.
+ leaky-device@12350000 {
+ compatible = "foo,i-leak-current";
+ reg = <0x12350000 0x1000>;
+ power-domains = <&power 0>;
+ };
+The node above defines a typical PM domain consumer device, which is located
+inside a PM domain with index 0 of a power controller represented by a node
+with the label "power".