Interrupt handler registration for multiple devices

Interrupt handler registration for multiple devices

[Rick Brown]

Hi,

I want to write a driver that will handle multiple devices. These
devices will share the IRQ line. Do I need to register my (same)
interrupt handler as many times as the number of devices(by calling
request_irq())?

Also an unrelated query. Can I sleep after a call to preempt_kernel()??

TIA,

Rick

Interrupt handler registration for multiple devices

[Rick Brown]

Hi,

I want to write a driver that will handle multiple devices. These
devices will share the IRQ line. Do I need to register my (same)
interrupt handler as many times as the number of devices(by calling
request_irq())?

Also an unrelated query. Can I sleep after a call to preempt_kernel()??

TIA,

Rick
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Re: Interrupt handler registration for multiple devices

[Octavian Purdila]

On Wednesday 30 August 2006 18:12, Rick Brown wrote:
> Hi,
>
> I want to write a driver that will handle multiple devices. These
> devices will share the IRQ line. Do I need to register my (same)
> interrupt handler as many times as the number of devices(by calling
> request_irq())?
>

No, once will suffice. However, you will need to check your devices registers 
and figure out which device triggered the interrupt.

tavi
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Re: Interrupt handler registration for multiple devices

[Alan Cox]

Ar Mer, 2006-08-30 am 20:42 +0530, ysgrifennodd Rick Brown:
> Hi,
> 
> I want to write a driver that will handle multiple devices. These
> devices will share the IRQ line. Do I need to register my (same)
> interrupt handler as many times as the number of devices(by calling
> request_irq())?

Up to you. If you are working with standard devices that need no special
handling to share interrupts (eg PCI bus), the device model makes it
more natural to do that and let the kernel call your handler once for
each device (passing a different dev_id).

Re: Interrupt handler registration for multiple devices

[Alan Cox]

Ar Mer, 2006-08-30 am 20:42 +0530, ysgrifennodd Rick Brown:
> Hi,
> 
> I want to write a driver that will handle multiple devices. These
> devices will share the IRQ line. Do I need to register my (same)
> interrupt handler as many times as the number of devices(by calling
> request_irq())?

Up to you. If you are working with standard devices that need no special
handling to share interrupts (eg PCI bus), the device model makes it
more natural to do that and let the kernel call your handler once for
each device (passing a different dev_id).


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