Devicetree

A devicetree is a hierarchical data structure primarily used to describe hardware. Zephyr uses devicetree in two main ways:

• to describe hardware to the Device Driver Model

• to provide that hardware’s initial configuration

This page links to a high level guide on devicetree as well as reference material.

Devicetree Guide

The pages in this section are a high-level guide to using devicetree for Zephyr development.

• Introduction to devicetree
  • Scope and purpose
  • Syntax and structure
  • Input and output files
• Design goals
  • Single source for hardware information
  • Source compatibility with other operating systems
• Devicetree bindings
  • Introduction to Devicetree Bindings
  • Devicetree bindings syntax
  • Rules for upstream bindings
• Devicetree access from C/C++
  • A note for Linux developers
  • Node identifiers
  • Node identifiers are not values
  • Property access
  • Other APIs
  • Device driver conveniences
  • Hardware specific APIs
  • Generated macros
• Phandles
  • Getting phandles
  • Using phandles
  • phandle-array properties
  • Specifier spaces
  • Associating properties with specifier spaces
  • Naming the cells in a specifier
  • See also
• The /zephyr,user node
  • Simple values
  • Devices
  • GPIOs
• Devicetree HOWTOs
  • Get your devicetree and generated header
  • Get a struct device from a devicetree node
  • Find a devicetree binding
  • Set devicetree overlays
  • Use devicetree overlays
  • Write device drivers using devicetree APIs
  • Device drivers that depend on other devices
  • Applications that depend on board-specific devices
• Troubleshooting devicetree
  • Try again with a pristine build directory
  • Make sure <devicetree.h> is included
  • undefined reference to __device_dts_ord_<N>
  • Make sure you’re using the right names
  • Look at the preprocessor output
  • Do not track macro expansion
  • Validate properties
  • Check for missing bindings
  • Errors with DT_INST_() APIs
• Devicetree versus Kconfig

Devicetree Reference

These pages contain reference material for Zephyr’s devicetree APIs and built-in bindings.

For the platform-independent details, see the Devicetree specification.

• Devicetree API
  • Generic APIs
    • Node identifiers and helpers
    • Property access
    • ranges property
    • reg property
    • interrupts property
    • For-each macros
    • Existence checks
    • Inter-node dependencies
    • Bus helpers
  • Instance-based APIs
  • Hardware specific APIs
    • CAN
    • Clocks
    • DMA
    • Fixed flash partitions
    • GPIO
    • IO channels
    • MBOX
    • Pinctrl (pin control)
    • PWM
    • Reset Controller
    • SPI
  • Chosen nodes
  • Zephyr-specific chosen nodes