diff --git a/Documentation/devicetree/bindings/fieldbus/arcx,anybus-controller.txt b/Documentation/devicetree/bindings/fieldbus/arcx,anybus-controller.txt new file mode 100644 index 000000000000..b1f9474f36d5 --- /dev/null +++ b/Documentation/devicetree/bindings/fieldbus/arcx,anybus-controller.txt @@ -0,0 +1,71 @@ +* Arcx Anybus-S controller + +This chip communicates with the SoC over a parallel bus. It is +expected that its Device Tree node is specified as the child of a node +corresponding to the parallel bus used for communication. + +Required properties: +-------------------- + + - compatible : The following chip-specific string: + "arcx,anybus-controller" + + - reg : three areas: + index 0: bus memory area where the cpld registers are located. + index 1: bus memory area of the first host's dual-port ram. + index 2: bus memory area of the second host's dual-port ram. + + - reset-gpios : the GPIO pin connected to the reset line of the controller. + + - interrupts : two interrupts: + index 0: interrupt connected to the first host + index 1: interrupt connected to the second host + Generic interrupt client node bindings are described in + interrupt-controller/interrupts.txt + +Optional: use of subnodes +------------------------- + +The card connected to a host may need additional properties. These can be +specified in subnodes to the controller node. + +The subnodes are identified by the standard 'reg' property. Which information +exactly can be specified depends on the bindings for the function driver +for the subnode. + +Required controller node properties when using subnodes: +- #address-cells: should be one. +- #size-cells: should be zero. + +Required subnode properties: +- reg: Must contain the host index of the card this subnode describes: + <0> for the first host on the controller + <1> for the second host on the controller + Note that only a single card can be plugged into a host, so the host + index uniquely describes the card location. + +Example of usage: +----------------- + +This example places the bridge on top of the i.MX WEIM parallel bus, see: +Documentation/devicetree/bindings/bus/imx-weim.txt + +&weim { + controller@0,0 { + compatible = "arcx,anybus-controller"; + reg = <0 0 0x100>, <0 0x400000 0x800>, <1 0x400000 0x800>; + reset-gpios = <&gpio5 2 GPIO_ACTIVE_HIGH>; + interrupt-parent = <&gpio1>; + interrupts = <1 IRQ_TYPE_LEVEL_LOW>, <5 IRQ_TYPE_LEVEL_LOW>; + /* fsl,weim-cs-timing is a i.MX WEIM bus specific property */ + fsl,weim-cs-timing = <0x024400b1 0x00001010 0x20081100 + 0x00000000 0xa0000240 0x00000000>; + /* optional subnode for a card plugged into the first host */ + #address-cells = <1>; + #size-cells = <0>; + card@0 { + reg = <0>; + /* card specific properties go here */ + }; + }; +};