From: Shenwei Wang <Shenwei.Wang@freescale.com>
To: Thomas Gleixner <tglx@linutronix.de>
CC: "shawn.guo@linaro.org" <shawn.guo@linaro.org>,
        "jason@lakedaemon.net" <jason@lakedaemon.net>,
        "sudeep.holla@arm.com" <sudeep.holla@arm.com>,
        "linux-arm-kernel@lists.infradead.org" 
	<linux-arm-kernel@lists.infradead.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Huang Anson <Anson.Huang@freescale.com>
Subject: RE: [PATCH 1/1] irqchip: imx-gpcv2: Simplify the implemenation
Thread-Topic: [PATCH 1/1] irqchip: imx-gpcv2: Simplify the implemenation
Thread-Index: AQHQ4BhnQCw9/HJgNUCrRbRu4Kf4sJ4ecbkwgAAvUoCAAAIqMA==
Date: Wed, 26 Aug 2015 19:05:18 +0000
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> -----Original Message-----
> From: Thomas Gleixner [mailto:tglx@linutronix.de]
> > > > +
> > > >  	if (sources)
> > > > -		*sources = imx_gpcv2_instance->wakeup_sources;
> > > > +		*sources = cd->wakeup_sources;
> > > >
> > > >  	return IMR_NUM;
> > >
> > > You do not need the intermediate storage at all.
> > >
> > > u32 imx_gpcv2_get_wakeup_source(u32 *sources) {
> > > 	if (sources) {
> > > 		for (i = 0; i < IMR_NUM; i++) {
> > > 			reg = cd->gpc_base + cd->cpu2wakeup + i * 4;
> > > 			sources[i] = readl_relaxed(reg);
> > > 		}
> > > 	}
> > > 	....
> >
> > Using the intermediate storage here can make the caller a little
> > easier, because the caller does not need to malloc the memory before the call.
> > Especially the caller does not even know how many memory to allocate
> > In the beginning.
> 
> Fair enough, but why do you need that case where sources can be NULL just to
> return IMR_NUM?

The intention is to get the IMR_NUM only. But so far no user uses this feature.

Thanks,
Shenwei

> Thanks,
> 
> 	tglx

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