1* Generic 8-bits shift register GPIO driver
2
3Required properties:
4- compatible: Should contain one of the following:
5    "fairchild,74hc595"
6    "nxp,74lvc594"
7- reg : chip select number
8- gpio-controller : Marks the device node as a gpio controller.
9- #gpio-cells : Should be two.  The first cell is the pin number and
10  the second cell is used to specify the gpio polarity:
11      0 = active high
12      1 = active low
13- registers-number: Number of daisy-chained shift registers
14
15Optional properties:
16- enable-gpios: GPIO connected to the OE (Output Enable) pin.
17
18Example:
19
20gpio5: gpio5@0 {
21	compatible = "fairchild,74hc595";
22	reg = <0>;
23	gpio-controller;
24	#gpio-cells = <2>;
25	registers-number = <4>;
26	spi-max-frequency = <100000>;
27};
28