Question on setting up external interrupt for P1020 (MPC8xxx) with device tree
scottwood at freescale.com
Sat Feb 12 08:56:44 EST 2011
On Fri, 11 Feb 2011 14:07:26 -0500
Kenny Ho <kho at belairnetworks.com> wrote:
> I am trying to write a device driver that uses an external interrupt
> (one of the 16 irq lines) for the Freescale P1020 processor and I hope
> some of you can help. Am I suppose to setup a separate node in the dts
> and look for that node in my driver to setup the interrupt?
Ideally, yes. It's good to describe your device with a node even if it
doesn't have interrupts.
> Or does the > dts interrupt declaration belong to the interrupt-controller
> declaration? I noticed the mpc8xxx_gpio driver defined its own irq_chip
> but I thought that may be because each gpio pin can trigger an
Right, it's because gpio is an interrupt controller, not just a user of one.
> Do I need to define my own irq_chip structure for my device
> even if I am using one of the hard irq lines?
No. If the device's node describes the interrupt correctly, you can use
irq_of_parse_and_map() on the device node to get a virtual irq that you can
pass to request_irq().
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