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From:   Thomas Gleixner <tglx@linutronix.de>
To:     Bjorn Helgaas <helgaas@kernel.org>
Cc:     Marc Gonzalez <marc.w.gonzalez@free.fr>,
        Aman Sharma <amanharitsh123@gmail.com>,
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Subject: Re: [PATCH 4/5] pci: handled return value of platform_get_irq correctly
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Date:   Wed, 18 Mar 2020 14:42:48 +0100
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Bjorn,

Bjorn Helgaas <helgaas@kernel.org> writes:
> On Fri, Mar 13, 2020 at 04:56:42PM -0500, Bjorn Helgaas wrote:
>> On Fri, Mar 13, 2020 at 10:05:58PM +0100, Thomas Gleixner wrote:
>> > >   I think the best pattern is:
>> > >
>> > >     irq = platform_get_irq(pdev, i);
>> > >     if (irq < 0)
>> > >       return irq;
>> > 
>> > Careful. 0 is not a valid interrupt.
>> 
>> Should callers of platform_get_irq() check for a 0 return value?
>> About 900 of them do not.

I don't know what I was looking at.

platform_get_irq() does the right thing already, so checking for irq < 0
is sufficient.

Sorry for the confusion!

Thanks,

        tglx