Question on MPC52xx IRQ[123] pins

Grant Likely grant.likely at
Tue Dec 22 10:16:18 EST 2009

On Mon, Dec 21, 2009 at 3:30 PM, Bill Gatliff <bgat at> wrote:
> gpio_get_value() on them.  There isn't any existing code that I can find
> that allows you to read the states of IRQ pins, be it under gpiolib or
> otherwise.  And I think the reason for that is that there's no way to
> actually read the states of those pins at all--- the hardware just
> doesn't work that way.

Correct.  IRQ2 can only be used as IRQ2.  It cannot be used a GPIO.
(Well, I suppose you *could* try to hack into the interrupt controller
driver and fetch the pin state that way; but I don't know if you can
read the state of masked out IRQ pins, and it sure would be ugly.)


Grant Likely, B.Sc., P.Eng.
Secret Lab Technologies Ltd.

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