Messages in this thread | | | Date | Fri, 10 Aug 2012 10:15:55 +0100 | From | Russell King - ARM Linux <> | Subject | Re: [PATCH v2] gpio: Add Avionic Design N-bit GPIO expander support |
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On Fri, Aug 10, 2012 at 10:41:58AM +0200, Linus Walleij wrote: > On Fri, Aug 10, 2012 at 10:35 AM, Thierry Reding > <thierry.reding@avionic-design.de> wrote: > >> Consult the following article on LWN: > >> http://lwn.net/Articles/470820/ > >> > >> Then grep your gitlog and you'll see we got rid of it from ARM. > > > > Then why is there still the following in arch/arm/include/asm/irq.h? > > > > /* > > * Use this value to indicate lack of interrupt > > * capability > > */ > > #ifndef NO_IRQ > > #define NO_IRQ ((unsigned int)(-1)) > > #endif > > That's a question for Russell but I think it's basically there for > old platforms, on a "don't use it"-basis. (Maybe a comment could > be good.)
Just don't use it. It's there for old stuff which still needs fixing.
New code should not use it, and should test for one of:
irq <= 0 irq == 0
And new code should set irq = 0 to indicate a lack of interrupt.
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