1* Synopsys DesignWare APB GPIO controller 2 3Required properties: 4- compatible : Should contain "snps,dw-apb-gpio" 5- reg : Address and length of the register set for the device. 6- #address-cells : should be 1 (for addressing port subnodes). 7- #size-cells : should be 0 (port subnodes). 8 9The GPIO controller has a configurable number of ports, each of which are 10represented as child nodes with the following properties: 11 12Required properties: 13- compatible : "snps,dw-apb-gpio-port" 14- gpio-controller : Marks the device node as a gpio controller. 15- #gpio-cells : Should be two. The first cell is the pin number and 16 the second cell is used to specify the gpio polarity: 17 0 = active high 18 1 = active low 19- reg : The integer port index of the port, a single cell. 20 21Optional properties: 22- interrupt-controller : The first port may be configured to be an interrupt 23controller. 24- #interrupt-cells : Specifies the number of cells needed to encode an 25 interrupt. Shall be set to 2. The first cell defines the interrupt number, 26 the second encodes the triger flags encoded as described in 27 Documentation/devicetree/bindings/interrupt-controller/interrupts.txt 28- interrupts : The interrupts to the parent controller raised when GPIOs 29 generate the interrupts. If the controller provides one combined interrupt 30 for all GPIOs, specify a single interrupt. If the controller provides one 31 interrupt for each GPIO, provide a list of interrupts that correspond to each 32 of the GPIO pins. When specifying multiple interrupts, if any are unconnected, 33 use the interrupts-extended property to specify the interrupts and set the 34 interrupt controller handle for unused interrupts to 0. 35- snps,nr-gpios : The number of pins in the port, a single cell. 36- resets : Reset line for the controller. 37 38Example: 39 40gpio: gpio@20000 { 41 compatible = "snps,dw-apb-gpio"; 42 reg = <0x20000 0x1000>; 43 #address-cells = <1>; 44 #size-cells = <0>; 45 46 porta: gpio-controller@0 { 47 compatible = "snps,dw-apb-gpio-port"; 48 gpio-controller; 49 #gpio-cells = <2>; 50 snps,nr-gpios = <8>; 51 reg = <0>; 52 interrupt-controller; 53 #interrupt-cells = <2>; 54 interrupt-parent = <&vic1>; 55 interrupts = <0>; 56 }; 57 58 portb: gpio-controller@1 { 59 compatible = "snps,dw-apb-gpio-port"; 60 gpio-controller; 61 #gpio-cells = <2>; 62 snps,nr-gpios = <8>; 63 reg = <1>; 64 }; 65}; 66