Linux Device Driver to disable/enable keyboard

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Theory:

 As we have seen in our earlier posts, that there are three registers for keyboard controller.

  • Control Register (0x64) -- Write Operation
  • Data Register (0x60) -- Write/Read Operation
  • Status Register (0x60) -- Read Operation
Process to disable Keyboard:
  • Wait until the keyboard controller is not busy by reading the status register
  • Send the command 0xAD to Control Register
Process to Enable Keyboard:
  • Wait until the keyboard controller is not busy by reading the status register
  • Send the command 0xAE to Control Register.
Code:



Output:


Notes:

 We have loaded the module using the command "sleep 1 && insmod ./kbd_disable.ko". If you try only "insmod ./kbd_disable.ko", the keyboard will disable at "Enter Press", so the console will be continuously receiving Enter Press Keys, until keyboard gets enabled back

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