1NXP LPC18xx/43xx GPIO controller Device Tree Bindings
2-----------------------------------------------------
3
4Required properties:
5- compatible		: Should be "nxp,lpc1850-gpio"
6- reg			: List of addresses and lengths of the GPIO controller
7			  register sets
8- reg-names		: Should be "gpio", "gpio-pin-ic", "gpio-group0-ic" and
9			  "gpio-gpoup1-ic"
10- clocks		: Phandle and clock specifier pair for GPIO controller
11- resets		: Phandle and reset specifier pair for GPIO controller
12- gpio-controller	: Marks the device node as a GPIO controller
13- #gpio-cells 		: Should be two:
14			  - The first cell is the GPIO line number
15			  - The second cell is used to specify polarity
16- interrupt-controller	: Marks the device node as an interrupt controller
17- #interrupt-cells	: Should be two:
18			  - The first cell is an interrupt number within
19			    0..9 range, for GPIO pin interrupts it is equal
20			    to 'nxp,gpio-pin-interrupt' property value of
21			    GPIO pin configuration, 8 is for GPIO GROUP0
22			    interrupt, 9 is for GPIO GROUP1 interrupt
23			  - The second cell is used to specify interrupt type
24
25Optional properties:
26- gpio-ranges		: Mapping between GPIO and pinctrl
27
28Example:
29#define LPC_GPIO(port, pin)	(port * 32 + pin)
30#define LPC_PIN(port, pin)	(0x##port * 32 + pin)
31
32gpio: gpio@400f4000 {
33	compatible = "nxp,lpc1850-gpio";
34	reg = <0x400f4000 0x4000>, <0x40087000 0x1000>,
35	      <0x40088000 0x1000>, <0x40089000 0x1000>;
36	reg-names = "gpio", "gpio-pin-ic",
37		    "gpio-group0-ic", "gpio-gpoup1-ic";
38	clocks = <&ccu1 CLK_CPU_GPIO>;
39	resets = <&rgu 28>;
40	gpio-controller;
41	#gpio-cells = <2>;
42	interrupt-controller;
43	#interrupt-cells = <2>;
44	gpio-ranges =	<&pinctrl LPC_GPIO(0,0)  LPC_PIN(0,0)  2>,
45			...
46			<&pinctrl LPC_GPIO(7,19) LPC_PIN(f,5)  7>;
47};
48
49gpio_joystick {
50	compatible = "gpio-keys";
51	...
52
53	button0 {
54		...
55		interrupt-parent = <&gpio>;
56		interrupts = <1 IRQ_TYPE_EDGE_BOTH>;
57		gpios = <&gpio LPC_GPIO(4,8) GPIO_ACTIVE_LOW>;
58	};
59};
60