Documentation/devicetree/bindings/leds/leds-bcm6328.yaml

Source file repositories/reference/linux-study-clean/Documentation/devicetree/bindings/leds/leds-bcm6328.yaml

File Facts

System
Linux kernel
Corpus path
Documentation/devicetree/bindings/leds/leds-bcm6328.yaml
Extension
.yaml
Size
10542 bytes
Lines
401
Domain
Support Tooling And Documentation
Bucket
Documentation
Inferred role
Support Tooling And Documentation: configuration, schema, or hardware description
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.

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# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
%YAML 1.2
---
$id: http://devicetree.org/schemas/leds/leds-bcm6328.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#

title: LEDs connected to Broadcom BCM6328 controller

maintainers:
  - Álvaro Fernández Rojas <noltari@gmail.com>

description: |
  This controller is present on BCM6318, BCM6328, BCM6362 and BCM63268.
  In these SoCs it's possible to control LEDs both as GPIOs or by hardware.
  However, on some devices there are Serial LEDs (LEDs connected to a 74x164
  controller), which can either be controlled by software (exporting the 74x164
  as spi-gpio. See
  Documentation/devicetree/bindings/gpio/fairchild,74hc595.yaml), or by hardware
  using this driver.
  Some of these Serial LEDs are hardware controlled (e.g. ethernet LEDs) and
  exporting the 74x164 as spi-gpio prevents those LEDs to be hardware
  controlled, so the only chance to keep them working is by using this driver.

  BCM6328 LED controller has a HWDIS register, which controls whether a LED
  should be controlled by a hardware signal instead of the MODE register value,
  with 0 meaning hardware control enabled and 1 hardware control disabled. This
  is usually 1:1 for hardware to LED signals, but through the activity/link
  registers you have some limited control over rerouting the LEDs (as
  explained later in brcm,link-signal-sources). Even if a LED is hardware
  controlled you are still able to make it blink or light it up if it isn't,
  but you can't turn it off if the hardware decides to light it up. For this
  reason, hardware controlled LEDs aren't registered as LED class devices.

  Each LED is represented as a sub-node of the brcm,bcm6328-leds device.

properties:
  compatible:
    const: brcm,bcm6328-leds

  reg:
    maxItems: 1

  brcm,serial-leds:
    type: boolean
    description: Enables Serial LEDs.

  brcm,serial-mux:
    type: boolean
    description: Enables Serial LEDs multiplexing.

  brcm,serial-clk-low:
    type: boolean
    description: Makes clock signal active low.

  brcm,serial-dat-low:
    type: boolean
    description: Makes data signal active low.

  brcm,serial-shift-inv:
    type: boolean
    description: Inverts Serial LEDs shift direction.

  "#address-cells":
    const: 1

  "#size-cells":
    const: 0

patternProperties:
  "@[a-f0-9]+$":

Annotation

Implementation Notes