On Fri, Sep 18, 2015 at 09:55:24AM +0200, Daniel Lezcano wrote: > On 09/17/2015 12:19 PM, Caesar Wang wrote: > > > > > >在 2015年09月17日 18:06, Daniel Lezcano 写道: > >>On 09/17/2015 11:28 AM, Caesar Wang wrote: > >>>Hi Daniel, > >>> > >>> > >>>在 2015年09月17日 17:11, Daniel Lezcano 写道: > >>>> > >>>>Hi Caesar, > >>>> > >>>> > >>>>On 09/17/2015 09:51 AM, Caesar Wang wrote: > >>>>>Build the arm64 SoCs (e.g.: RK3368) on Rockchip platform, > >>>>>There are some failure with build up on timer driver for rockchip. > >>>>> > >>>>>logs: > >>>>>... > >>>>>drivers/clocksource/rockchip_timer.c:156:13: error: 'NO_IRQ' > >>>>>undeclared > >>>> > >>>>I think the NO_IRQ definition is missing for ARM64. > >>> > >>>Yep, Maybe better to compatible if we don't use the 'NO_IRQ', > >> > >>Hmm, after digging into drivers/of/irq.c and kernel/irq/irqdomain.c > >> > >>when there is an error it returns zero. So NO_IRQ and -1 are not > >>correct and on the other side zero can be a valid irq. That sounds a > >>little bit fuzzy to me. > > > >I believe the 'NO_IRQ' is better select if 'NO_IRQ' is defined on ARM64 > >platform. > > > > irq = irq_of_parse_and_map(np, 0); > > > > if (irq == NO_IRQ) > >... > >Also, that's ok if we instead of the 'irq < 0' or '!irq' , right? > > > Hi Caesar, > > so regarding Thomas and Russel answers, let's replace NO_IRQ by '!irq'. ^
Definitely in this case. irq_create_of_mapping() and therefore irq_of_parse_and_map() both return _zero_ when they fail, not whatever happens to be NO_IRQ on a particular architecture. New code should _never_ be making any use of NO_IRQ. That's why I said: "Modern drivers should _all_ be using !irq to detect invalid IRQs, and not using NO_IRQ." -- FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up according to speedtest.net. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/