1* Generic 8-bits shift register GPIO driver 2 3Required properties: 4- compatible : Should be "fairchild,74hc595" 5- reg : chip select number 6- gpio-controller : Marks the device node as a gpio controller. 7- #gpio-cells : Should be two. The first cell is the pin number and 8 the second cell is used to specify the gpio polarity: 9 0 = active high 10 1 = active low 11- registers-number: Number of daisy-chained shift registers 12 13Example: 14 15gpio5: gpio5@0 { 16 compatible = "fairchild,74hc595"; 17 reg = <0>; 18 gpio-controller; 19 #gpio-cells = <2>; 20 registers-number = <4>; 21 spi-max-frequency = <100000>; 22}; 23