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Date: Wed, 19 Mar 2014 17:59:27 +0900
From: Cho KyongHo <pullip.cho@samsung.com>
To: Tomasz Figa <t.figa@samsung.com>
Cc: Sachin Kamat <sachin.kamat@linaro.org>,
        Linux ARM Kernel <linux-arm-kernel@lists.infradead.org>,
        Linux DeviceTree <devicetree@vger.kernel.org>,
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        Kukjin Kim <kgene.kim@samsung.com>,
        Prathyush <prathyush.k@samsung.com>,
        Rahul Sharma <rahul.sharma@samsung.com>,
        Sylwester Nawrocki <s.nawrocki@samsung.com>,
        Varun Sethi <Varun.Sethi@freescale.com>
Subject: Re: [PATCH v11 10/27] iommu/exynos: use managed device helper functions
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On Tue, 18 Mar 2014 16:14:53 +0100, Tomasz Figa wrote:
> On 18.03.2014 12:09, Cho KyongHo wrote:
> > On Fri, 14 Mar 2014 20:52:43 +0530, Sachin Kamat wrote:
> >> Hi KyongHo,
> >>
> >> On 14 March 2014 10:35, Cho KyongHo <pullip.cho@samsung.com> wrote:
> >>> This patch uses managed device helper functions in the probe().
> >>>
> >>> Signed-off-by: Cho KyongHo <pullip.cho@samsung.com>
> >>> ---
> >> [snip]
> >>
> >>> +       data->clk = devm_clk_get(dev, "sysmmu");
> >>> +       if (IS_ERR(data->clk)) {
> >>> +               dev_info(dev, "No gate clock found!\n");
> >>> +               data->clk = NULL;
> >>> +       }
> >>
> >> Why aren't you returning from here upon error?
> >
> > It is for the case of a System MMU which does not need clock gating.
> >
> 
> Are there really such cases?
> 

Yes.
Especially in the case of initial stage of new SoC development.

I have experianced some software workaround for H/W restriction
needs prevention of clock gating for some devices.

Regards,

KyongHo