1*c66ec88fSEmmanuel VadotLantiq SoC External Bus memory mapped GPIO controller 2*c66ec88fSEmmanuel Vadot 3*c66ec88fSEmmanuel VadotBy attaching hardware latches to the EBU it is possible to create output 4*c66ec88fSEmmanuel Vadotonly gpios. This driver configures a special memory address, which when 5*c66ec88fSEmmanuel Vadotwritten to outputs 16 bit to the latches. 6*c66ec88fSEmmanuel Vadot 7*c66ec88fSEmmanuel VadotThe node describing the memory mapped GPIOs needs to be a child of the node 8*c66ec88fSEmmanuel Vadotdescribing the "lantiq,localbus". 9*c66ec88fSEmmanuel Vadot 10*c66ec88fSEmmanuel VadotRequired properties: 11*c66ec88fSEmmanuel Vadot- compatible : Should be "lantiq,gpio-mm-lantiq" 12*c66ec88fSEmmanuel Vadot- reg : Address and length of the register set for the device 13*c66ec88fSEmmanuel Vadot- #gpio-cells : Should be two. The first cell is the pin number and 14*c66ec88fSEmmanuel Vadot the second cell is used to specify optional parameters (currently 15*c66ec88fSEmmanuel Vadot unused). 16*c66ec88fSEmmanuel Vadot- gpio-controller : Marks the device node as a gpio controller. 17*c66ec88fSEmmanuel Vadot 18*c66ec88fSEmmanuel VadotOptional properties: 19*c66ec88fSEmmanuel Vadot- lantiq,shadow : The default value that we shall assume as already set on the 20*c66ec88fSEmmanuel Vadot shift register cascade. 21*c66ec88fSEmmanuel Vadot 22*c66ec88fSEmmanuel VadotExample: 23*c66ec88fSEmmanuel Vadot 24*c66ec88fSEmmanuel Vadotlocalbus@0 { 25*c66ec88fSEmmanuel Vadot #address-cells = <2>; 26*c66ec88fSEmmanuel Vadot #size-cells = <1>; 27*c66ec88fSEmmanuel Vadot ranges = <0 0 0x0 0x3ffffff /* addrsel0 */ 28*c66ec88fSEmmanuel Vadot 1 0 0x4000000 0x4000010>; /* addsel1 */ 29*c66ec88fSEmmanuel Vadot compatible = "lantiq,localbus", "simple-bus"; 30*c66ec88fSEmmanuel Vadot 31*c66ec88fSEmmanuel Vadot gpio_mm0: gpio@4000000 { 32*c66ec88fSEmmanuel Vadot compatible = "lantiq,gpio-mm"; 33*c66ec88fSEmmanuel Vadot reg = <1 0x0 0x10>; 34*c66ec88fSEmmanuel Vadot gpio-controller; 35*c66ec88fSEmmanuel Vadot #gpio-cells = <2>; 36*c66ec88fSEmmanuel Vadot lantiq,shadow = <0x77f> 37*c66ec88fSEmmanuel Vadot }; 38*c66ec88fSEmmanuel Vadot} 39