The Linux driver implementer’s API guide

The kernel offers a wide variety of interfaces to support the development of device drivers. This document is an only somewhat organized collection of some of those interfaces — it will hopefully get better over time! The available subsections can be seen below.

Table of contents

• Driver Basics
  • Driver Entry and Exit points
  • Driver device table
  • Delaying, scheduling, and timer routines
  • Wait queues and Wake events
  • High-resolution timers
  • Workqueues and Kevents
  • Internal Functions
  • Reference counting
  • Atomics
  • Kernel objects manipulation
  • Kernel utility functions
  • Device Resource Management
• Device drivers infrastructure
  • The Basic Device Driver-Model Structures
  • Device Drivers Base
  • Device Drivers DMA Management
  • Device drivers PnP support
  • Userspace IO devices
• CPU and Device Power Management
  • CPU Idle Time Management
  • Device Power Management Basics
  • Suspend/Hibernation Notifiers
  • Device Power Management Data Types
• The Common Clk Framework
  • Introduction and interface split
  • Common data structures and api
  • Hardware clk implementations
  • Supporting your own clk hardware
  • Disabling clock gating of unused clocks
  • Locking
• Bus-Independent Device Accesses
  • Introduction
  • Memory Mapped IO
  • Port Space Accesses
  • Public Functions Provided
• Device connections
  • Introduction
  • Usage
  • API
• Buffer Sharing and Synchronization
  • Shared DMA Buffers
  • Reservation Objects
  • DMA Fences
• Device links
  • Usage
  • Limitations
  • Examples
  • Alternatives
  • Implementation
  • State machine
  • API
• Component Helper for Aggregate Drivers
  • API
• Message-based devices
  • Fusion message devices
• Sound Devices
• Frame Buffer Library
  • Frame Buffer Memory
  • Frame Buffer Colormap
  • Frame Buffer Video Mode Database
  • Frame Buffer Macintosh Video Mode Database
  • Frame Buffer Fonts
• Voltage and current regulator API
  • Introduction
  • Consumer driver interface
  • Regulator driver interface
  • Machine interface
  • API reference
• Industrial I/O
  • Introduction
  • Core elements
  • Buffers
  • Triggers
  • Triggered Buffers
  • HW consumer
• Input Subsystem
  • Input core
  • Multitouch Library
  • Polled input devices
  • Matrix keyboards/keypads
  • Sparse keymap support
• Linux USB API
  • The Linux-USB Host Side API
  • USB Gadget API for Linux
  • USB Anchors
  • USB bulk streams
  • USB core callbacks
  • USB DMA
  • USB Request Block (URB)
  • Power Management for USB
  • USB hotplugging
  • USB device persistence during system suspend
  • USB Error codes
  • Writing USB Device Drivers
  • Synopsys DesignWare Core SuperSpeed USB 3.0 Controller
  • Writing a MUSB Glue Layer
  • USB Type-C connector class
  • API for USB Type-C Alternate Mode drivers
  • USB3 debug port
• Firewire (IEEE 1394) driver Interface Guide
  • Introduction and Overview
  • Firewire char device data structures
  • Firewire device probing and sysfs interfaces
  • Firewire core transaction interfaces
  • Firewire Isochronous I/O interfaces
• The Linux PCI driver implementer’s API guide
  • PCI Support Library
  • PCI Hotplug Support Library
  • PCI Peer-to-Peer DMA Support
• Serial Peripheral Interface (SPI)
• I²C and SMBus Subsystem
• I3C subsystem
  • I3C protocol
  • I3C device driver API
  • I3C master controller driver API
• High Speed Synchronous Serial Interface (HSI)
  • Introduction
  • HSI Subsystem in Linux
  • hsi-char Device
  • The kernel HSI API
• Error Detection And Correction (EDAC) Devices
  • Main Concepts used at the EDAC subsystem
  • Memory Controllers
  • PCI Controllers
  • EDAC Blocks
• SCSI Interfaces Guide
  • Introduction
  • SCSI upper layer
  • SCSI mid layer
  • SCSI lower layer
• libATA Developer’s Guide
  • Introduction
  • libata Driver API
  • Error handling
  • libata Library
  • libata Core Internals
  • libata SCSI translation/emulation
  • ATA errors and exceptions
  • ata_piix Internals
  • sata_sil Internals
  • Thanks
• target and iSCSI Interfaces Guide
  • Introduction and Overview
  • Target core device interfaces
  • Target core transport interfaces
  • Target-supported userspace I/O
  • iSCSI helper functions
  • iSCSI boot information
  • iSCSI transport class
  • iSCSI TCP interfaces
• MTD NAND Driver Programming Interface
  • Introduction
  • Known Bugs And Assumptions
  • Documentation hints
  • Basic board driver
  • Advanced board driver functions
  • Filesystem support
  • Tools
  • Constants
  • Structures
  • Public Functions Provided
  • Internal Functions Provided
  • Credits
• Parallel Port Devices
• 16x50 UART Driver
• Pulse-Width Modulation (PWM)
• W1: Dallas’ 1-wire bus
  • W1 API internal to the kernel
• RapidIO Subsystem Guide
  • Introduction
  • Known Bugs and Limitations
  • RapidIO driver interface
  • Internals
  • Credits
• Writing s390 channel device drivers
  • Introduction
  • The css bus
  • The ccw bus
  • The ccwgroup bus
  • Generic interfaces
• VME Device Drivers
  • Driver registration
  • Resource management
  • Master windows
  • Slave windows
  • DMA channels
  • Interrupts
  • Location monitors
  • Slot Detection
  • Bus Detection
  • VME API
• Linux 802.11 Driver Developer’s Guide
  • Introduction
  • cfg80211 subsystem
  • mac80211 subsystem (basics)
  • mac80211 subsystem (advanced)
• The Userspace I/O HOWTO
  • About this document
  • About UIO
  • Writing your own kernel module
  • Writing a driver in userspace
  • Generic PCI UIO driver
  • Generic Hyper-V UIO driver
  • Further information
• Linux Firmware API
  • Introduction
  • Firmware API core features
  • request_firmware API
  • Other Firmware Interfaces
• PINCTRL (PIN CONTROL) subsystem
  • Top-level interface
  • Pin groups
  • Pin configuration
  • Interaction with the GPIO subsystem
  • PINMUX interfaces
  • What is pinmuxing?
  • Pinmux conventions
  • Pinmux drivers
  • Pin control interaction with the GPIO subsystem
  • GPIO mode pitfalls
  • Board/machine configuration
  • Complex mappings
  • Pin control requests from drivers
  • Drivers needing both pin control and GPIOs
  • System pin control hogging
  • Runtime pinmuxing
• General Purpose Input/Output (GPIO)
  • Introduction
  • GPIO Descriptor Driver Interface
  • GPIO Descriptor Consumer Interface
  • GPIO Mappings
  • Subsystem drivers using GPIO
  • Legacy GPIO Interfaces
  • Core
  • ACPI support
  • Device tree support
  • Device-managed API
  • sysfs helpers
• Miscellaneous Devices
• DMAEngine documentation
  • DMAEngine documentation
  • DMAEngine client documentation
  • DMA Test documentation
  • PXA DMA documentation
• Linux kernel SLIMbus support
  • Overview
• SoundWire Documentation
  • SoundWire Subsystem Summary
  • Audio Stream in SoundWire
  • SoundWire Error Handling
  • SoundWire Locking
• FPGA Subsystem
  • Introduction
  • FPGA Manager
  • FPGA Bridge
  • FPGA Region
  • In-kernel API for FPGA Programming