Re: [PATCH 1/2] GPIO: Add driver for Zynq GPIO controller

From: SÃren Brinkmann
Date: Mon Apr 07 2014 - 15:02:45 EST


On Mon, 2014-03-31 at 11:23AM +0200, Ulf Hansson wrote:
> On 27 March 2014 16:25, Harini Katakam <harinik@xxxxxxxxxx> wrote:
[...]
> > +static int __maybe_unused zynq_gpio_runtime_suspend(struct device *dev)
> > +{
> > + struct platform_device *pdev = to_platform_device(dev);
> > + struct zynq_gpio *gpio = platform_get_drvdata(pdev);
> > +
> > + clk_disable(gpio->clk);
>
> You should be able can use clk_disable_unprepare() here.
>
> > +
> > + return 0;
> > +}
> > +
> > +static int __maybe_unused zynq_gpio_runtime_resume(struct device *dev)
> > +{
> > + struct platform_device *pdev = to_platform_device(dev);
> > + struct zynq_gpio *gpio = platform_get_drvdata(pdev);
> > +
> > + return clk_enable(gpio->clk);
>
> You should be able can use clk_prepare_enable() here.

Is there some common practice regarding this? As I understand it, we
want to ensure the clock to be gated during suspend, which should happen
with clk_disable(). Why would we also unprepare the clock? We are highly
likely to use it again once we resume.

Thanks,
SÃren


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