Eighth Reading notes

Chapter 8

Code reuse:1, static reuse : Put the code to be reused in other files, if you want to use some features,include the corresponding header file to

2, dynamic reuse: One linux driver can use resources from another Linux driver

To uninstall a Linux driver module that cannot be uninstalled due to an exception condition:

1. Initialization function crash: Clear the reference counter of the current Linux driver module to 0

2. The Unload function is blocked: Replace the original unload function with an empty unload function

Buzzer is also called PWM(pulse width modulation), the basic principle is to control the buzzer by pulse to open and stop

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Eighth Reading notes