✅ Linux Driver Development with Raspberry Pi - Full Tutorial Series Roadmap

SECTION 0 - Introduction & Preparation

1. Introduction to the Series

• What the series covers
• Tools, requirements
• Recommended references (inc. Linux Device Drivers 3rd Edition)

2. Understanding the Linux Kernel

• Kernel architecture
• User space vs kernel space

3. Linux Device Drivers Overview

SECTION 1 - Raspberry Pi Setup & Development Environment

4. Raspberry Pi Setup

• Installing Raspberry Pi OS (64-bit)
• Enabling SSH
• Installing kernel headers
• Recommended directory layout

5. First Kernel Module

• A simple hello.ko
• Makefile
• insmod, rmmod, modinfo
• Kernel print levels (Log levels)

SECTION 2 - Character Device Driver Foundations

6. Character Device Driver Basics

• Allocating major/minor numbers
• cdev_init, cdev_add
• Manual mknod vs udev auto-creation
• File operations overview

7. File Operations Deep Dive

• open, release, read, write
• copy_to_user, copy_from_user
• Using file->private_data

8. IOCTL Implementation

• Defining IOCTL commands
• Handling IOCTL in driver
• User application examples

9. Memory Allocation Mechanisms

• kmalloc, kzalloc, vmalloc
• GFP flags
• Slab allocator overview

10. Kernel Linked Lists

• list_head, iterating, adding, deleting
• Using linked lists in drivers

SECTION 3 - GPIO, Interrupts, Timers

11. GPIO Control

• Request/release GPIO
• Set/get GPIO state

12. GPIO Interrupt Handling

• request_irq
• IRQ numbers
• Debouncing
• Top-half vs bottom-half

13. High Resolution Timers (hrtimer)

• One-shot, periodic timers

SECTION 4 - I2C & SPI Drivers

14. I2C Subsystem Basics

• Linux I2C architecture
• Client vs adapter vs driver
• Registering an I2C driver
• Creating a device via /sys/bus/i2c/devices

15. BMP180 Sensor Driver (Complete Example)

• Read/write registers
• Calibration
• Temperature & pressure reading
• Exposing sensor values to user space

16. SPI Subsystem Basics

• SPI architecture
• Full duplex transfers
• SPI message & transfer structs

SECTION 5 - Concurrency & Synchronization

17. Kernel Threads (kthread)

• Creating, running, stopping threads
• Thread loop best practices

18. Wait Queues, Poll, Fasync

• Blocking/non-blocking I/O
• Implementing .poll() & select()
• Async notification using fasync

19. Kernel Synchronization Techniques

• Mutex
• Spinlock
• Completion
• When to use which

20. Workqueues & Bottom Halves

• Deferred execution
• System vs dedicated workqueues
• Comparison with tasklets

SECTION 6 - Linux Device Model & Sysfs

21. Linux Device Model

• Devices, drivers, buses, classes
• Probe/remove lifecycle
• Hotplug & Uevents (plug/unplug)

22. Sysfs Interface

• Device attributes
• Creating and removing sysfs files
• Sysfs class interfaces (/sys/class/mydriver)

23. Debugfs for Driver Debugging

• Creating debugfs entries
• Live introspection of driver variables
• Differences from sysfs

SECTION 7 - Device Tree & Raspberry Pi Overlays

24. Device Tree Introduction

• Why Device Tree exists
• Structure of .dts and .dtsi
• Status, compatible, reg, gpios

25. Writing Raspberry Pi Device Tree Overlays

• Overlay structure
• Adding nodes dynamically
• Applying overlays live

26. Device Tree - GPIO Example

• Creating a GPIO LED/button node
• Binding to your driver
• Reading GPIO from DT

27. Device Tree - I2C Device

• Adding BMP180 in DT
• Custom compatible string
• Passing configuration via DT

28. Platform Driver

• Introduction to platform bus
• Platform_device vs platform_driver
• Useful for non-I2C/SPI devices

29. Pin Control & Pinmux

• Pin configuration in DT
• Alternate functions on Raspberry Pi pins

30. OF (Open Firmware) Parsing

• Using DT helper APIs
• Parsing strings, ints, gpios from DT

SECTION 8 - Advanced Topics

31. Misc Device Driver

• Easiest way to expose /dev/mydevice
• When to prefer over char device

32. Regmap API

• Excellent for I2C/SPI register-mapped chips
• Reduces boilerplate
• Cache & sync

33. DMA Engine Basics & DMA memcpy

• DMA vs CPU copy
• DMA mapping APIs
• Simple DMA example

34. Accessing Files from Kernel (Safely)

• filp_open, kernel_read, kernel_write
• Kernel warnings & limitations
• Practical example: writing logs to SD card

35. Memory Mapping (mmap)

• Expose kernel buffers to user space
• Example: custom framebuffer
• Page faults inside driver

36. Industrial I/O (IIO) Framework

• When to use IIO
• Creating an IIO device
• Reading ADC-like data

37. Sending Signals to User Space

• Real-time signals
• Notify app when an event occurs
• Example: IRQ → signal to application

SECTION 9 - Serial Drivers

38. UART (Serial) Driver

• UART on Raspberry Pi
• Writing a minimal UART driver
• Using termios from user space

SECTION 10 - Final Project

39. Complete Raspberry Pi Kernel Driver Project

• A sophisticated final driver combining everything:
• Device Tree overlay
• Char device with IOCTL
• Sysfs interface
• GPIO + interrupt + poll
• High-resolution timer
• Optional I2C or SPI communication
• debugfs runtime variables
• User-space test application

40. Packaging & Publishing

• Versioning
• DKMS support
• GitHub best practices
• Share as a Linux kernel module package