Linux Device Drivers: Kernel Level Programming – 2021 Release

Module 00: Course Introduction

Module 01: What’s a Device Driver?

• Why Device Drivers?
• User Space and Kernel Space
• Process Context and Interrupt Context
• User Space I/O Apis
• Types of Devices
• The/dev/Directory
• Exercise: Explore the /dev Directory

Module 02: Kernel Loadable Modules

• What is a Kernel Loadable Module?
• Module Utilities
• Building a Module
• Modules and the GPL

Module 03: Demo: Kernel Modules

Exercise: Build and Run a Module

Module 04: Basic Character Driver

• Registering and Initializing a Driver
• The File Operations Table, fops
• Driver Example
• Mutual Exclusion, the Mutex
• Exercise: Build and Run simple_char

Module 05: Basic Driver Code Review

• Exercise: Build and Run Basic Driver

Module 06: Debugging Kernel Code

• printk
• strace
• Pseudo file systems
  • /proc
  • /sys
• ioctl

Module 07: Debugging Demo

• strace
• /proc Files
• Create a /proc File
• Create a /debugfs File
• ioctl

Module 08: KGDB

• Configuring the Kernel for KGDB
  • Make xconfig
• Set up Second Virtual Machine
  • Pseudo Serial Port
  • Shared Folder
• “Magic” sys Request Trigger
• Debugging Kernel Modules

Module 09: KGDB Demo

• Exercise: Explore KGDB

Module 10: Blocking I/O

• The Wait Queue
• Putting a Process to Sleep
• The misc Device
• The seq File Interface
• Poll and Select
• Asynchronous Notification

Module 11: Blocking I/O Demo and Code Review

• Exercise: Build and Run Blocking Driver
• Exercise: Find the Bug

Module 12: Accessing Hardware

• Side Effects and Compiler Optimization
• I/O APIs
• Barriers

Module 13: Interrupt Handling

• Interrupt Context
• Registering an Interrupt Handler, the IRQ Flags
• Probing for the Interrupt Source
• The Bottom Half – tasklets and workqueues

Module 14: I/O in User Space, the /sys file system

Module 15: /sys Demo

Module 16: The Linux Driver Model

• Overview, Motivation
• Busses
• Devices
• Drivers
• kobject
• sysfs

Module 17: Demo: lxr

Module 18: Code Review: lddbus.c

• Exercise: Build and run lddbus.c

Module 19: Managing Time

• jiffies
• Current Time
• Implementing Time Delays
• The Timer Callback

Module 20: Demo: Time

• Exercise: Build and Run jit.c

Module 21: Synchronization

• Mutexes
• Spinlocks

Module 22: Memory Allocation

• kmalloc() and kfree()
• kmalloc() flags
• The Slab Allocator
• get_free_pages()
• The Buddy Algorithm
• vmalloc()

Module 23: Demo: Memory Allocation

Module 24: Block Devices

• The Block Subsystem
• I/O Schedulers
• Device Registration
• The Request Queue and Function

Module 25: Code Review: simple_block.c

• Exercise: Build and Run simple_block.c

Module 26: PCI Devices

• PCI Addressing and Bridging
• PCI Tools
• Accessing Configuration Space
• PCI Data Structures and Macros

Module 27: Code Review: ne2kpci.c

Module 28: Network Devices

• Device Registration
• The Socket Buffer
• NAPI – the “New” API

Module 29: 29: Code Review: lib8390.c, 8390.c & ne2kpci.c

Module 30: USB Devices

• USB Structure and Characteristics
• USB Tools
• Device Classes
• USB Data Structures and Macros
• USB Request Block, URB

Module 31: Device Trees

• The Problem
• Background
• Device Tree Structure
• “Compatible” Property
• Device Tree and Linux

Module 32: Review