Documentation/devicetree/bindings/pinctrl/brcm,nsp-gpio.txt
Source file repositories/reference/linux-study-clean/Documentation/devicetree/bindings/pinctrl/brcm,nsp-gpio.txt
File Facts
- System
- Linux kernel
- Corpus path
Documentation/devicetree/bindings/pinctrl/brcm,nsp-gpio.txt- Extension
.txt- Size
- 1983 bytes
- Lines
- 81
- Domain
- Support Tooling And Documentation
- Bucket
- Documentation
- Inferred role
- Support Tooling And Documentation: documentation
- Status
- atlas-only
Why This File Exists
Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
- Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
Dependency Surface
- No C-style include directives detected by the generator.
Detected Declarations
- No top-level syscall, struct, function, initcall, or export declaration detected by the generator.
Annotated Snippet
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 {
Annotation
- Atlas domain: Support Tooling And Documentation / Documentation.
- Implementation status: atlas-only.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.