linux-zen-desktop/Documentation/devicetree/bindings/pinctrl/brcm,nsp-gpio.txt

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2023-08-30 17:31:07 +02:00
Broadcom Northstar plus (NSP) GPIO/PINCONF Controller
Required properties:
- compatible:
Must be "brcm,nsp-gpio-a"
- reg:
Should contain the register physical address and length for each of
GPIO base, IO control registers
- #gpio-cells:
Must be two. The first cell is the GPIO pin number (within the
controller's pin space) and the second cell is used for the following:
bit[0]: polarity (0 for active high and 1 for active low)
- gpio-controller:
Specifies that the node is a GPIO controller
- ngpios:
Number of gpios supported (58x25 supports 32 and 58x23 supports 24)
Optional properties:
- interrupts:
Interrupt ID
- interrupt-controller:
Specifies that the node is an interrupt controller
- gpio-ranges:
Specifies the mapping between gpio controller and pin-controllers pins.
This requires 4 fields in cells defined as -
1. Phandle of pin-controller.
2. GPIO base pin offset.
3 Pin-control base pin offset.
4. number of gpio pins which are linearly mapped from pin base.
Supported generic PINCONF properties in child nodes:
- pins:
The list of pins (within the controller's own pin space) that properties
in the node apply to. Pin names are "gpio-<pin>"
- bias-disable:
Disable pin bias
- bias-pull-up:
Enable internal pull up resistor
- bias-pull-down:
Enable internal pull down resistor
- drive-strength:
Valid drive strength values include 2, 4, 6, 8, 10, 12, 14, 16 (mA)
Example:
gpioa: gpio@18000020 {
compatible = "brcm,nsp-gpio-a";
reg = <0x18000020 0x100>,
<0x1803f1c4 0x1c>;
#gpio-cells = <2>;
gpio-controller;
ngpios = <32>;
gpio-ranges = <&pinctrl 0 0 31>;
interrupt-controller;
interrupts = <GIC_SPI 85 IRQ_TYPE_LEVEL_HIGH>;
/* Hog a few default settings */
pinctrl-names = "default";
pinctrl-0 = <&led>;
led: led {
pins = "gpio-1";
bias-pull-up;
};
pwr: pwr {
gpio-hog;
gpios = <3 1>;
output-high;
};
};