Linux Device Driver Projects

This repository contains a collection of Linux device driver examples designed for learning and experimentation on a standard laptop. These projects cover various aspects of Linux kernel development, including character and block devices, interrupt handling, and interfacing with user space through procfs and sysfs.

Projects Overview

1. Basic Character Device Driver

Objective: Implement a simple character device driver that supports basic read and write operations.

Key Features:

• Registers a character device with the Linux kernel.
• Supports operations like open, close, read, and write.
• Creates a /dev/simplechar file for user-space interaction.

2. Pseudo-Random Number Generator Driver

Objective: Develop a character device driver that returns pseudo-random numbers.

Key Features:

• Generates random numbers using kernel space functions.
• Provides random numbers through read operations on the /dev/randomnum file.

3. Virtual Block Device Driver

Objective: Create a virtual block device that acts as a ramdisk.

Key Features:

• Implements a block device driver managing a memory buffer.
• Supports read and write operations through the block device interface.
• Mountable as a filesystem using a file like /dev/vramdisk.

4. LED Control Simulation Driver

Objective: Simulate an LED control driver that toggles "LED" state via user commands.

Key Features:

• Implements simple IOCTL commands to control LED states.
• Simulates LED on/off and blink actions, logging the state to the kernel log.

5. ProcFS/SysFS Interface Driver

Objective: Interact with user space via the /proc or /sys filesystem.

Key Features:

• Creates entries in /proc or /sys to display and control driver states.
• Allows read/write operations from user space to modify driver behavior.

6. Simulated Temperature Sensor Driver

Objective: Develop a driver that simulates temperature sensor readings.

Key Features:

• Returns simulated temperature readings in Celsius or Fahrenheit.
• Updates temperature values periodically using kernel timers.
• Allows mode switching via IOCTL.

7. Interrupt Handling Driver

Objective: Create a driver that handles simulated interrupts.

Key Features:

• Implements an Interrupt Service Routine (ISR).
• Triggers interrupts using kernel timers or software interrupts.
• Logs interrupt handling events using dmesg.

8. Keyboard Input Logger Driver

Objective: Log keyboard inputs to the kernel log or a specific file.

Key Features:

• Captures and logs keyboard events.
• Filters specific key inputs.
• Logs keypress and key release events.

Getting Started

Prerequisites

• Linux Kernel Headers: Ensure that your system has the Linux kernel headers installed.
• Development Tools: Install gcc, make, and other development tools required for compiling kernel modules.

Setup and Compilation

1. Clone the repository:

   git clone https://github.com/yourusername/LinuxDeviceDriver.git
   cd LinuxDeviceDriver

2. Navigate to the desired project directory:

   cd BasicCharacterDriver

3. Compile the driver:

   make

4. Load the driver:

   sudo insmod simplechar.ko

5. Interact with the driver:

   echo "Hello, Driver!" > /dev/simplechar
   cat /dev/simplechar

6. Unload the driver:

   sudo rmmod simplechar

Note

• Always ensure you have a backup or are working in a safe environment (e.g., a virtual machine) when testing drivers.
• Modifying kernel space can potentially cause system instability.

Contribution

Feel free to contribute to this repository by adding new drivers, improving existing code, or enhancing documentation.

License

This project is licensed under the MIT License. See the LICENSE file for details.