mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-22 20:23:57 +08:00
bb37baeaaf
Device tree binding documentation for Broadcom NSP GPIO-a Signed-off-by: Yendapally Reddy Dhananjaya Reddy <yrdreddy@broadcom.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
81 lines
1.9 KiB
Plaintext
81 lines
1.9 KiB
Plaintext
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;
|
|
};
|
|
};
|