1* Samsung Exynos Power Domains 2 3Exynos processors include support for multiple power domains which are used 4to gate power to one or more peripherals on the processor. 5 6Required Properties: 7- compatible: should be one of the following. 8 * samsung,exynos4210-pd - for exynos4210 type power domain. 9- reg: physical base address of the controller and length of memory mapped 10 region. 11- #power-domain-cells: number of cells in power domain specifier; 12 must be 0. 13 14Optional Properties: 15- clocks: List of clock handles. The parent clocks of the input clocks to the 16 devices in this power domain are set to oscclk before power gating 17 and restored back after powering on a domain. This is required for 18 all domains which are powered on and off and not required for unused 19 domains. 20- clock-names: The following clocks can be specified: 21 - oscclk: Oscillator clock. 22 - clkN: Input clocks to the devices in this power domain. These clocks 23 will be reparented to oscclk before swithing power domain off. 24 Their original parent will be brought back after turning on 25 the domain. Maximum of 4 clocks (N = 0 to 3) are supported. 26 - asbN: Clocks required by asynchronous bridges (ASB) present in 27 the power domain. These clock should be enabled during power 28 domain on/off operations. 29- power-domains: phandle pointing to the parent power domain, for more details 30 see Documentation/devicetree/bindings/power/power_domain.txt 31 32Node of a device using power domains must have a power-domains property 33defined with a phandle to respective power domain. 34 35Example: 36 37 lcd0: power-domain-lcd0 { 38 compatible = "samsung,exynos4210-pd"; 39 reg = <0x10023C00 0x10>; 40 #power-domain-cells = <0>; 41 }; 42 43 mfc_pd: power-domain@10044060 { 44 compatible = "samsung,exynos4210-pd"; 45 reg = <0x10044060 0x20>; 46 clocks = <&clock CLK_FIN_PLL>, <&clock CLK_MOUT_USER_ACLK333>; 47 clock-names = "oscclk", "clk0"; 48 #power-domain-cells = <0>; 49 }; 50 51See Documentation/devicetree/bindings/power/power_domain.txt for description 52of consumer-side bindings. 53