[RFC/PATCH v2 10/13] dt: omap4: panda board: set clock freq for i2c devices

Cousson, Benoit b-cousson at ti.com
Wed Aug 24 05:03:55 EST 2011


> From: G, Manjunath Kondaiah<manjugk at ti.com>
> To: devicetree-discuss at lists.ozlabs.org
> CC: linux-omap at vger.kernel.org, linux-arm-kernel at lists.infradead.org
>
>
> Update omap4 panda dts file with required clock frequencies
> for the i2c client devices existing on panda board.
>
> Signed-off-by: G, Manjunath Kondaiah<manjugk at ti.com>
> ---
>    arch/arm/boot/dts/omap4-panda.dts |   16 ++++++++++++++++
>    1 files changed, 16 insertions(+), 0 deletions(-)
>
> diff --git a/arch/arm/boot/dts/omap4-panda.dts
> b/arch/arm/boot/dts/omap4-panda.dts
> index c28aa95..6b831ca 100644
> --- a/arch/arm/boot/dts/omap4-panda.dts
> +++ b/arch/arm/boot/dts/omap4-panda.dts
> @@ -3,4 +3,20 @@
>    / {
>    	model = "TI OMAP4 PandaBoard";
>    	compatible = "ti,omap4-panda", "ti,omap4430";
> +
> +	i2c1 {
> +		clock-frequency =<400000>;
> +	};
> +
> +	i2c2 {
> +		clock-frequency =<400000>;
> +	};
> +
> +	i2c3 {
> +		clock-frequency =<400000>;
> +	};
> +
> +	i2c4 {
> +		clock-frequency =<400000>;
> +	};
>    };

Are you sure that this patch is setting the expected frequency?
I see 100kHz in the boot log even with that patch.

I took me some time to find the proper syntax, but in order to reference 
an existing node, you have to use &i2c1 at the top level of the file. If 
you check the output of the DTC compiler, you will see the property at 
the proper node.

Benoit



More information about the devicetree-discuss mailing list