driver: gpio: nct38xx: Add NCT38XX gpio driver support
NCT38XX series, which are i2c-based chips, support a different number
of GPIO functionality. For NCT3807, it has 2 GPIO ports on the same i2c
device address. For NCT3808, it has 2 GPIO ports on different i2c
device addresses. This commit adds NCT38XX GPIO driver support &
provides the interrupt handler for the share alert pin.
The following is NCT3807 devicetree node example:
```
&i2c0_0 {
nct3807_0: nct3807@70 {
#address-cells = <1>;
#size-cells = <0>;
compatible = "nuvoton,nct38xx-gpio";
reg = <0x70>;
label = "NCT3807_0";
gpio@0 {
compatible = "nuvoton,nct38xx-gpio-port";
reg = <0x0>;
label = "NCT3807_0_GPIO0";
gpio-controller;
#gpio-cells = <2>;
ngpios = <8>;
pin_mask = <0xff>;
pinmux_mask = <0xf7>;
};
gpio@1 {
compatible = "nuvoton,nct38xx-gpio-port";
reg = <0x1>;
label = "NCT3807_0_GPIO1";
gpio-controller;
#gpio-cells = <2>;
ngpios = <8>;
pin_mask = <0xff>;
};
};
};
```
Signed-off-by: Wealian Liao <WHLIAO@nuvoton.com>
