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Date: Mon, 17 Aug 2015 13:37:36 +0300
From: Laurentiu Tudor <b10716@freescale.com>
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To: <linuxppc-dev@lists.ozlabs.org>, Ran Shalit <ranshalit@gmail.com>
Subject: Re: using general IRQs
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On 08/10/2015 10:48 AM, Ran Shalit wrote:
> Hello,
> 
> MPC8349 has general IRQ numbered 0-7,
> It is required to bind these IRQs with some routine , i.e. they are
> not used with any specific driver.
> 
> - Should they be configured as gpios in device tree so that we can use
> the gpio as irq in linux ? Is there any example ?

If it's a gpio then yes, you need to use it as a gpio. Not familiar with MPC8349,
but newer FSL chips can select between gpio or irq through a RCW field (IRQ_BASE?).

Note that for gpios there's special apis, such as:  of_get_gpio(), gpio_request_one() a.s.o.
Also you'll need to update your device tree node to something like:

  intc2@0{
   compatible = "intc2";
   reg = <0 0x1000>;
   gpios = <&gpio0 4 0>;
  };

See Documentation/gpio.txt for more info.

---
Best Regards, Laurentiu