Re: [PATCH 4/7] can/at91: don't check platform_get_irq's return valueagainst zero

From: Wolfgang Grandegger
Date: Wed Dec 16 2009 - 13:58:54 EST

Uwe Kleine-König wrote:
> On Wed, Dec 16, 2009 at 05:27:03PM +0100, Wolfgang Grandegger wrote:
>> Uwe Kleine-König wrote:
>>> platform_get_irq returns -ENXIO on failure, so !irq was probably
>>> always true. Better use (int)irq <= 0. Note that a return value of
>>> zero is still handled as error even though this could mean irq0.
>> But only on ARM, which is the only platform still using the infamous
>> NO_IRQ (=-1). As this is a driver for ARM hardware, using irq == NO_IRQ
>> would make sense, though.
> This has nothing to do with NO_IRQ. You could do:

Right, sorry for the noise.

> - if (!res || !irq) {
> + if (!res || irq <= (int)NO_IRQ) {
> but this looks too ugly. (IMHO using NO_IRQ is already ugly.)
> Still, before my patch platform_get_irq return 0 was an error and if
> this should be handled as irq0 this is a separate issue that should be
> fixed in a separate patch.

"irq <= 0" seems then the best solution. Will add my signed-off-by to
the patch.


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