1* 74XX MMIO GPIO driver 2 3Required properties: 4- compatible: Should contain one of the following: 5 "ti,741g125": for 741G125 (1-bit Input), 6 "ti,741g174": for 741G74 (1-bit Output), 7 "ti,742g125": for 742G125 (2-bit Input), 8 "ti,7474" : for 7474 (2-bit Output), 9 "ti,74125" : for 74125 (4-bit Input), 10 "ti,74175" : for 74175 (4-bit Output), 11 "ti,74365" : for 74365 (6-bit Input), 12 "ti,74174" : for 74174 (6-bit Output), 13 "ti,74244" : for 74244 (8-bit Input), 14 "ti,74273" : for 74273 (8-bit Output), 15 "ti,741624" : for 741624 (16-bit Input), 16 "ti,7416374": for 7416374 (16-bit Output). 17- reg: Physical base address and length where IC resides. 18- gpio-controller: Marks the device node as a gpio controller. 19- #gpio-cells: Should be two. The first cell is the pin number and 20 the second cell is used to specify the GPIO polarity: 21 0 = Active High, 22 1 = Active Low. 23 24Example: 25 ctrl: gpio@30008004 { 26 compatible = "ti,74174"; 27 reg = <0x30008004 0x1>; 28 gpio-controller; 29 #gpio-cells = <2>; 30 }; 31