Shared Interrupts Question (2.4)

[Kent Borg]

On Thu, May 08, 2003 at 02:14:26PM -0700, Dale Farnsworth wrote:
> Create and register a board-specific interrupt driver.  Assign it
> a range of irqs (non-conflicting with the main interrupt driver).
> When called with an irq outside its range, the board-specific driver
> routines forward the call to the main driver.

Cool, cool...

> The board-specific driver does a request_irq at init time for the
> one main irq it is multiplexing.

What does my handler on the main irq do?  Perhaps nothing?

I am figuring I supply my own get_irq call, and it returns one of this
new interrupt range, or if none, calls the previous get_irq.  If I
never let the main irq number come back, my handler on the main irq
never gets called, right?  If so, why am calling request_irq in the
first place?  To keep the system from puking on spurious interrupts?
(But if I answer the get_irq, and if I never answer the main irq
number, how would it know?)


Thanks,

-kb, the Kent who thinks he is getting close.

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