[PATCH 04/17] powerpc: mpic: use IRQCHIP_SKIP_SET_WAKE instead of redundant mpic_irq_set_wake

[Wang Dongsheng]

> -----Original Message-----
> From: linux-kernel-owner at vger.kernel.org [mailto:linux-kernel-
> owner at vger.kernel.org] On Behalf Of Thomas Gleixner
> Sent: Wednesday, September 23, 2015 11:49 AM
> To: Wang Dongsheng-B40534
> Cc: Wood Scott-B07421; Sudeep Holla; linux-pm at vger.kernel.org; linux-
> kernel at vger.kernel.org; Rafael J. Wysocki; Benjamin Herrenschmidt; Paul
> Mackerras; Michael Ellerman; Jia Hongtao-B38951; Marc Zyngier; linuxppc-
> dev at lists.ozlabs.org
> Subject: RE: [PATCH 04/17] powerpc: mpic: use IRQCHIP_SKIP_SET_WAKE instead of
> redundant mpic_irq_set_wake
> 
> On Wed, 23 Sep 2015, Wang Dongsheng wrote:
> > > On Mon, 2015-09-21 at 16:47 +0100, Sudeep Holla wrote:
> > > > mpic_irq_set_wake return -ENXIO for non FSL MPIC and sets IRQF_NO_SUSPEND
> > > > flag for FSL ones. enable_irq_wake already returns -ENXIO if irq_set_wak
> > > > is not implemented. Also there's no need to set the IRQF_NO_SUSPEND flag
> > > > as it doesn't guarantee wakeup for that interrupt.
> > > >
> >
> > Non-freescale return -ENXIO, is there any issue? If non-freescale
> > platform does not support it, but IPs still use
> > enable/disable_irq_wake, we should return a error number.
> 
> You can just set IRQCHIP_SKIP_SET_WAKE for FSL chips and not for the
> others.
> 
> > @Scott:
> > If set this flag we cannot keep a irq as a wakeup source when system going to
> > SUSPEND or MEM.
> >
> > irq_set_wake() means we can set this irq as a wake source.
> > IRQCHIP_SKIP_SET_WAKE is ignore irq_set_wake() feature.
> 
> Nonsense. IRQCHIP_SKIP_SET_WAKE merily tells the core not to bail on
> !chip->irq_set_wake(), but its still marking the interrupt as wakeup
> source and therefor not masking it on suspend.
> 

Sorry, I just check irq_set_irq_wake() code, right, IRQCHIP_SKIP_SET_WAKE also can
going to irqd_set to mask IRQD_WAKEUP_STATE.

Yes, this flag just skip the irq_set_wake() not this feature.

Regards,
-Dongsheng