[PATCH/RFC] ARM: shmobile: lager: Add I2C2 clock frequency to device tree

Simon Horman horms at verge.net.au
Thu Oct 30 21:49:30 PDT 2014


On Thu, Oct 30, 2014 at 02:54:18PM +0100, Wolfram Sang wrote:
> On Thu, Oct 30, 2014 at 02:55:20PM +0900, Simon Horman wrote:
> > From: Ryo Kataoka <ryo.kataoka.wt at renesas.com>
> > 
> > Signed-off-by: Ryo Kataoka <ryo.kataoka.wt at renesas.com>
> > [simon: rebased]
> > Signed-off-by: Simon Horman <horms+renesas at verge.net.au>
> > ---
> > Based on the renesas-devel-20141030-v3.18-rc2 branch of my renesas tree
> > 
> > If this is useful I wonder if it is should be set in the lager board DTS
> > file instead of the r8a7790 SoC DTSI file.
> 
> ? This IS set in the .dts and not the .dtsi.

So it is. I got confused between several similar patches.

> 400kHz should never be set in a .dtsi. Not all i2c slave devices support
> it. 100kHz is the default which all slaves need to support. But since
> I've seen cases where the board needs to lower even further because of
> board design issues, I'm getting reluctant to set even 100kHz in dtsi
> files in general.

Thanks, I will drop this patch.

> 
> > 
> > 
> >  arch/arm/boot/dts/r8a7790-lager.dts | 1 +
> >  1 file changed, 1 insertion(+)
> > 
> > diff --git a/arch/arm/boot/dts/r8a7790-lager.dts b/arch/arm/boot/dts/r8a7790-lager.dts
> > index 830f2e8..32c7e48 100644
> > --- a/arch/arm/boot/dts/r8a7790-lager.dts
> > +++ b/arch/arm/boot/dts/r8a7790-lager.dts
> > @@ -426,6 +426,7 @@
> >  
> >  &iic2	{
> >  	status = "ok";
> > +	clock-frequency = <400000>;
> >  	pinctrl-0 = <&iic2_pins>;
> >  	pinctrl-names = "default";
> >  
> > -- 
> > 2.1.1
> > 





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