Documentation/devicetree/bindings/gpio/gpio-74x164.txt

   1 * Generic 8-bits shift register GPIO driver
   2
   3 Required 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
  15 Example:
  16
  17 gpio5: gpio5@0 {
  18         compatible = "fairchild,74hc595";
  19         reg = <0>;
  20         gpio-controller;
  21         #gpio-cells = <2>;
  22         registers-number = <4>;
  23         spi-max-frequency = <100000>;
  24 };