Based on kernel version 4.16.1. Page generated on 2018-04-09 11:52 EST.
1 Simple Power-Managed Bus 2 ======================== 3 4 A Simple Power-Managed Bus is a transparent bus that doesn't need a real 5 driver, as it's typically initialized by the boot loader. 6 7 However, its bus controller is part of a PM domain, or under the control of a 8 functional clock. Hence, the bus controller's PM domain and/or clock must be 9 enabled for child devices connected to the bus (either on-SoC or externally) 10 to function. 11 12 While "simple-pm-bus" follows the "simple-bus" set of properties, as specified 13 in the Devicetree Specification, it is not an extension of "simple-bus". 14 15 16 Required properties: 17 - compatible: Must contain at least "simple-pm-bus". 18 Must not contain "simple-bus". 19 It's recommended to let this be preceded by one or more 20 vendor-specific compatible values. 21 - #address-cells, #size-cells, ranges: Must describe the mapping between 22 parent address and child address spaces. 23 24 Optional platform-specific properties for clock or PM domain control (at least 25 one of them is required): 26 - clocks: Must contain a reference to the functional clock(s), 27 - power-domains: Must contain a reference to the PM domain. 28 Please refer to the binding documentation for the clock and/or PM domain 29 providers for more details. 30 31 32 Example: 33 34 bsc: bus@fec10000 { 35 compatible = "renesas,bsc-sh73a0", "renesas,bsc", 36 "simple-pm-bus"; 37 #address-cells = <1>; 38 #size-cells = <1>; 39 ranges = <0 0 0x20000000>; 40 reg = <0xfec10000 0x400>; 41 interrupts = <0 39 IRQ_TYPE_LEVEL_HIGH>; 42 clocks = <&zb_clk>; 43 power-domains = <&pd_a4s>; 44 };