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Date: Mon, 5 Dec 2011 18:45:22 +0000
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: Dave Martin <dave.martin@linaro.org>,
        Russell King - ARM Linux <linux@arm.linux.org.uk>,
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Subject: Re: [PATCH] ata: Don't use NO_IRQ in pata_of_platform driver
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> But as you illustrated, there is a large number of drivers that already 
> assume no IRQ is < 0, even if they don't use any IRQ #0 themselves.  
> That is a much bigger problem to fix.

And a much larger number assuming the reverse is true which are hiding
potential bugs on ARM.

Looking at the serial stuff the best checks appear to be looking at
"irq", "-1" and NO_IRQ.

For migration stuff that's doing broken things like

	if (irq < 0)

can be changed to

	if (irq <= 0)

and that can be done before NO_IRQ itself is nailed on ARM and PA-RISC.