diff --git a/Documentation/devicetree/bindings/reset/st,sti-powerdown.txt b/Documentation/devicetree/bindings/reset/st,sti-powerdown.txt new file mode 100644 index 000000000000..5ab26b7e9d35 --- /dev/null +++ b/Documentation/devicetree/bindings/reset/st,sti-powerdown.txt @@ -0,0 +1,47 @@ +STMicroelectronics STi family Sysconfig Peripheral Powerdown Reset Controller +============================================================================= + +This binding describes a reset controller device that is used to enable and +disable on-chip peripheral controllers such as USB and SATA, using +"powerdown" control bits found in the STi family SoC system configuration +registers. These have been grouped together into a single reset controller +device for convenience. + +The actual action taken when powerdown is asserted is hardware dependent. +However, when asserted it may not be possible to access the hardware's +registers and after an assert/deassert sequence the hardware's previous state +may no longer be valid. + +Please refer to reset.txt in this directory for common reset +controller binding usage. + +Required properties: +- compatible: Should be "st,-powerdown" + ex: "st,stih415-powerdown", "st,stih416-powerdown" +- #reset-cells: 1, see below + +example: + + powerdown: powerdown-controller { + #reset-cells = <1>; + compatible = "st,stih415-powerdown"; + }; + + +Specifying powerdown control of devices +======================================= + +Device nodes should specify the reset channel required in their "resets" +property, containing a phandle to the powerdown device node and an +index specifying which channel to use, as described in reset.txt + +example: + + usb1: usb@fe200000 { + resets = <&powerdown STIH41X_USB1_POWERDOWN>; + }; + +Macro definitions for the supported reset channels can be found in: + +include/dt-bindings/reset-controller/stih415-resets.h +include/dt-bindings/reset-controller/stih416-resets.h diff --git a/arch/arm/boot/dts/stih415.dtsi b/arch/arm/boot/dts/stih415.dtsi index d9c7dd1d95a4..19e29f4af9d6 100644 --- a/arch/arm/boot/dts/stih415.dtsi +++ b/arch/arm/boot/dts/stih415.dtsi @@ -10,6 +10,7 @@ #include "stih415-clock.dtsi" #include "stih415-pinctrl.dtsi" #include +#include / { L2: cache-controller { @@ -28,6 +29,11 @@ ranges; compatible = "simple-bus"; + powerdown: powerdown-controller { + #reset-cells = <1>; + compatible = "st,stih415-powerdown"; + }; + syscfg_sbc: sbc-syscfg@fe600000{ compatible = "st,stih415-sbc-syscfg", "syscon"; reg = <0xfe600000 0xb4>; diff --git a/include/dt-bindings/reset-controller/stih415-resets.h b/include/dt-bindings/reset-controller/stih415-resets.h new file mode 100644 index 000000000000..2d54e68c2d95 --- /dev/null +++ b/include/dt-bindings/reset-controller/stih415-resets.h @@ -0,0 +1,19 @@ +/* + * This header provides constants for the reset controller + * based peripheral powerdown requests on the STMicroelectronics + * STiH415 SoC. + */ +#ifndef _DT_BINDINGS_RESET_CONTROLLER_STIH415 +#define _DT_BINDINGS_RESET_CONTROLLER_STIH415 + +#define STIH415_EMISS_POWERDOWN 0 +#define STIH415_NAND_POWERDOWN 1 +#define STIH415_KEYSCAN_POWERDOWN 2 +#define STIH415_USB0_POWERDOWN 3 +#define STIH415_USB1_POWERDOWN 4 +#define STIH415_USB2_POWERDOWN 5 +#define STIH415_SATA0_POWERDOWN 6 +#define STIH415_SATA1_POWERDOWN 7 +#define STIH415_PCIE_POWERDOWN 8 + +#endif /* _DT_BINDINGS_RESET_CONTROLLER_STIH415 */