Question on setting up external interrupt for P1020 (MPC8xxx) with device tree

Hi,

 

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?  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
interrupt.  Do I need to define my own irq_chip structure for my device
even if I am using one of the hard irq lines?  

 

Regards,

Kenny