[PATCH 2/2] ARM: dts: ODROID i2c improvements

Tomasz Figa t.figa at samsung.com
Wed Jul 16 05:34:59 PDT 2014


On 16.07.2014 10:50, Daniel Drake wrote:
> Increase max i2c bus frequency beyond the default for faster
> data transfers. According to the manual, these faster speeds are
> only available when the board is wired up the right way. In this case,
> the vendor kernel has run at this speed for a long time.
> 
> sda-delay is needed for talking to RTC on PMIC, otherwise the i2c
> controller never sees an ACK. Strangely the other PMIC i2c slave (the
> main one) works fine even without this delay. I Chose value 100 to
> match the vendor kernel.
> 
> Signed-off-by: Daniel Drake <drake at endlessm.com>
> ---
>  arch/arm/boot/dts/exynos4412-odroid-common.dtsi | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/arch/arm/boot/dts/exynos4412-odroid-common.dtsi b/arch/arm/boot/dts/exynos4412-odroid-common.dtsi
> index cb6f55f..adadaf9 100644
> --- a/arch/arm/boot/dts/exynos4412-odroid-common.dtsi
> +++ b/arch/arm/boot/dts/exynos4412-odroid-common.dtsi
> @@ -134,6 +134,8 @@
>  	i2c at 13860000 {
>  		pinctrl-0 = <&i2c0_bus>;
>  		pinctrl-names = "default";
> +		samsung,i2c-sda-delay = <100>;
> +		samsung,i2c-max-bus-freq = <400000>;
>  		status = "okay";
>  
>  		usb3503: usb3503 at 08 {
> 

Reviewed-by: Tomasz Figa <t.figa at samsung.com>

--
Best regards,
Tomasz



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