diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/devicetree/bindings/arm/exynos/power_domain.txt | 13 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/power/power_domain.txt | 49 |
2 files changed, 55 insertions, 7 deletions
diff --git a/Documentation/devicetree/bindings/arm/exynos/power_domain.txt b/Documentation/devicetree/bindings/arm/exynos/power_domain.txt index 8b4f7b7fe88b..abde1ea8a119 100644 --- a/Documentation/devicetree/bindings/arm/exynos/power_domain.txt +++ b/Documentation/devicetree/bindings/arm/exynos/power_domain.txt @@ -8,6 +8,8 @@ Required Properties: * samsung,exynos4210-pd - for exynos4210 type power domain. - reg: physical base address of the controller and length of memory mapped region. +- #power-domain-cells: number of cells in power domain specifier; + must be 0. Optional Properties: - clocks: List of clock handles. The parent clocks of the input clocks to the @@ -29,6 +31,7 @@ Example: lcd0: power-domain-lcd0 { compatible = "samsung,exynos4210-pd"; reg = <0x10023C00 0x10>; + #power-domain-cells = <0>; }; mfc_pd: power-domain@10044060 { @@ -37,12 +40,8 @@ Example: clocks = <&clock CLK_FIN_PLL>, <&clock CLK_MOUT_SW_ACLK333>, <&clock CLK_MOUT_USER_ACLK333>; clock-names = "oscclk", "pclk0", "clk0"; + #power-domain-cells = <0>; }; -Example of the node using power domain: - - node { - /* ... */ - samsung,power-domain = <&lcd0>; - /* ... */ - }; +See Documentation/devicetree/bindings/power/power_domain.txt for description +of consumer-side bindings. diff --git a/Documentation/devicetree/bindings/power/power_domain.txt b/Documentation/devicetree/bindings/power/power_domain.txt new file mode 100644 index 000000000000..98c16672ab5f --- /dev/null +++ b/Documentation/devicetree/bindings/power/power_domain.txt @@ -0,0 +1,49 @@ +* 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 +current. + +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. + +Example: + + 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. + +Example: + + 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". |