Linux Device Driver for counting keyboard strokes

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For each key pressed on the keyboard, it generates two interrupts (pressed and release).

Code:

Output:


Notes:

 1. IRQ line 1 is assigned for keyboard, we register our handler to be called on keyboard interrupt by calling request_irq
2. IRQF_SHARED flag is used for sharing the keyboard interrupt
3. synchronize_irq waits for the specific handler to exit.


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