From mboxrd@z Thu Jan  1 00:00:00 1970
From: Cho KyongHo <pullip.cho-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
Subject: Re: [PATCH v11 10/27] iommu/exynos: use managed device helper
	functions
Date: Wed, 19 Mar 2014 17:59:27 +0900
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To: Tomasz Figa <t.figa-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
Cc: Linux DeviceTree <devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Linux Samsung SOC <linux-samsung-soc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Prathyush <prathyush.k-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>, Sachin Kamat <sachin.kamat-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>, Linux Kernel <linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Grant Grundler <grundler-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>, Linux IOMMU <iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org>, Kukjin Kim <kgene.kim-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>, Sylwester Nawrocki <s.nawrocki-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>, Varun Sethi <Varun.Sethi-KZfg59tc24xl57MIdRCFDg@public.gmane.org>, Antonios Motakis <a.motakis-lrHrjnjw1UfHK3s98zE1ajGjJy/sRE9J@public.gmane.org>, Linux ARM Kernel <linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org>, Rahul Sharma <rahul.sharma-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
List-Id: linux-samsung-soc@vger.kernel.org

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-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org> wrote:
> >>> This patch uses managed device helper functions in the probe().
> >>>
> >>> Signed-off-by: Cho KyongHo <pullip.cho-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
> >>> ---
> >> [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