%Interrupts
%Thadeu Cascardo

# Hardware interrupts

* Way to notify the processor an external event has happened
* Signal
* Concurrency

# Enable and disable

* local\\_irq\\_disable
* local\\_irq\\_enable
* local\\_irq\\_save
* local\\_irq\\_restore
* disable\\_irq(irq)
* enable\\_irq(irq)

# Request and Release

* request\\_irq(irq, handler, flags, name, dev)
* IRQF\\_SHARED
* IRQF\\_SAMPLE\\_RANDOM
* free\\_irq(irq, dev)

# Writing Handlers

* irqreturn\\_t handler(irq, dev)
* IRQ\\_NONE
* IRQ\\_HANDLE