From mboxrd@z Thu Jan  1 00:00:00 1970
From: andrew@lunn.ch (Andrew Lunn)
Date: Fri, 17 Aug 2012 00:10:00 +0200
Subject: PATCH Add support for the Iomega IX2-200 Device Tree
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Message-ID: <20120816221000.GG18145@lunn.ch>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

> the problem seems to be in this comming from this line:
> 
> button->gpio = of_get_gpio_flags(pp, 0, &flags);
> 
> in the function :
> 
> /*
>  * Translate OpenFirmware node properties into platform_data
>  */
> static struct gpio_keys_platform_data * __devinit
> 
> of the gpio_keys.c file or whatever that line links to. It does not
> know how to deal with some NULL reference as far as i can tell.

Do you mean this piece of code:

       while ((pp = of_get_next_child(node, pp))) {
                enum of_gpio_flags flags;

                if (!of_find_property(pp, "gpios", NULL)) {
                        pdata->nbuttons--;
                        dev_warn(dev, "Found button without gpios\n");
                        continue;
                }
                buttons[i].gpio = of_get_gpio_flags(pp, 0, &flags);

This would fit with:

[    5.981782] Unable to handle kernel NULL pointer dereference at
virtual address 00000004
  
since gpio is at offset 4 in buttons. What is the value of i when it
oppses? What is buttons[i]?

	Andrew