Subject: [PATCH] irq: bcm2835: Re-implement the hardware IRQ handler.

From: [email-masked] (Craig McGeachie)
Date: Wed, 25 Sep 2013 18:00:53 +1200

On 09/24/2013 03:38 PM, Stephen Warren wrote:
>> +#define BAD_IRQ_NUM	-1
>
> That should be 0; Using -1 for invalid IRQ is deprecated.

Could you please point me to something that describes this? I can't find 
anything that limits the internal representations used by the driver for 
an interrupt controller.  That, and the design of 
include/linux/irqdomain.h and kernel/irq/irqdomain.c implies that a 
0-based hwirq numbering scheme is the natural order of things.

Cheers,
Craig.