1*4882a593SmuzhiyunAspeed SGPIO controller Device Tree Bindings 2*4882a593Smuzhiyun-------------------------------------------- 3*4882a593Smuzhiyun 4*4882a593SmuzhiyunThis SGPIO controller is for ASPEED AST2500 SoC, it supports up to 80 full 5*4882a593Smuzhiyunfeatured Serial GPIOs. Each of the Serial GPIO pins can be programmed to 6*4882a593Smuzhiyunsupport the following options: 7*4882a593Smuzhiyun- Support interrupt option for each input port and various interrupt 8*4882a593Smuzhiyun sensitivity option (level-high, level-low, edge-high, edge-low) 9*4882a593Smuzhiyun- Support reset tolerance option for each output port 10*4882a593Smuzhiyun- Directly connected to APB bus and its shift clock is from APB bus clock 11*4882a593Smuzhiyun divided by a programmable value. 12*4882a593Smuzhiyun- Co-work with external signal-chained TTL components (74LV165/74LV595) 13*4882a593Smuzhiyun 14*4882a593SmuzhiyunRequired properties: 15*4882a593Smuzhiyun 16*4882a593Smuzhiyun- compatible : Should be one of 17*4882a593Smuzhiyun "aspeed,ast2400-sgpio", "aspeed,ast2500-sgpio" 18*4882a593Smuzhiyun- #gpio-cells : Should be 2, see gpio.txt 19*4882a593Smuzhiyun- reg : Address and length of the register set for the device 20*4882a593Smuzhiyun- gpio-controller : Marks the device node as a GPIO controller 21*4882a593Smuzhiyun- interrupts : Interrupt specifier, see interrupt-controller/interrupts.txt 22*4882a593Smuzhiyun- interrupt-controller : Mark the GPIO controller as an interrupt-controller 23*4882a593Smuzhiyun- ngpios : number of *hardware* GPIO lines, see gpio.txt. This will expose 24*4882a593Smuzhiyun 2 software GPIOs per hardware GPIO: one for hardware input, one for hardware 25*4882a593Smuzhiyun output. Up to 80 pins, must be a multiple of 8. 26*4882a593Smuzhiyun- clocks : A phandle to the APB clock for SGPM clock division 27*4882a593Smuzhiyun- bus-frequency : SGPM CLK frequency 28*4882a593Smuzhiyun 29*4882a593SmuzhiyunThe sgpio and interrupt properties are further described in their respective 30*4882a593Smuzhiyunbindings documentation: 31*4882a593Smuzhiyun 32*4882a593Smuzhiyun- Documentation/devicetree/bindings/gpio/gpio.txt 33*4882a593Smuzhiyun- Documentation/devicetree/bindings/interrupt-controller/interrupts.txt 34*4882a593Smuzhiyun 35*4882a593Smuzhiyun Example: 36*4882a593Smuzhiyun sgpio: sgpio@1e780200 { 37*4882a593Smuzhiyun #gpio-cells = <2>; 38*4882a593Smuzhiyun compatible = "aspeed,ast2500-sgpio"; 39*4882a593Smuzhiyun gpio-controller; 40*4882a593Smuzhiyun interrupts = <40>; 41*4882a593Smuzhiyun reg = <0x1e780200 0x0100>; 42*4882a593Smuzhiyun clocks = <&syscon ASPEED_CLK_APB>; 43*4882a593Smuzhiyun interrupt-controller; 44*4882a593Smuzhiyun ngpios = <8>; 45*4882a593Smuzhiyun bus-frequency = <12000000>; 46*4882a593Smuzhiyun }; 47