On Fri, 2014-10-17 at 11:27 +0200, Valentin Longchamp wrote:
> With "fsl-i2c" compatibility the i2c frequency is not set
> correctly, because it sets no prescaler. According to the AN2919 from
> Freescale and the QorIQ (P2041) documentation, the source clock is 1/2
> the platform clock. This implies that a prescaler of 2 must be used.
>
> This changes the compatibility of the qoriq-i2c .dtsi files to pick the
> mpc8543, which uses the same driver but sets the correct prescaler.
>
> Signed-off-by: Rainer Boschung <rainer.boschung@xxxxxxxxxxx>
> Signed-off-by: Valentin Longchamp <valentin.longchamp@xxxxxxxxxxx>
> ---
>
> arch/powerpc/boot/dts/fsl/qoriq-i2c-0.dtsi | 4 ++--
> arch/powerpc/boot/dts/fsl/qoriq-i2c-1.dtsi | 4 ++--
> 2 files changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/arch/powerpc/boot/dts/fsl/qoriq-i2c-0.dtsi b/arch/powerpc/boot/dts/fsl/qoriq-i2c-0.dtsi
> index 5f9bf7d..aa6c366 100644
> --- a/arch/powerpc/boot/dts/fsl/qoriq-i2c-0.dtsi
> +++ b/arch/powerpc/boot/dts/fsl/qoriq-i2c-0.dtsi
> @@ -36,7 +36,7 @@ i2c@118000 {
> #address-cells = <1>;
> #size-cells = <0>;
> cell-index = <0>;
> - compatible = "fsl-i2c";
> + compatible = "fsl,mpc8543-i2c", "fsl-i2c";
> reg = <0x118000 0x100>;
> interrupts = <38 2 0 0>;
> dfsrr;
> @@ -46,7 +46,7 @@ i2c@118100 {
> #address-cells = <1>;
> #size-cells = <0>;
> cell-index = <1>;
> - compatible = "fsl-i2c";
> + compatible = "fsl,mpc8543-i2c", "fsl-i2c";
> reg = <0x118100 0x100>;
> interrupts = <38 2 0 0>;
> dfsrr;
Are all chips that use this dtsi 100% compatible with mpc8543's i2c, or
just in ways the Linux driver cares about?
What about fsl,mpc8544-i2c, which has additional special handling in the
driver, but is only used in socrates.dts (not mpc8544ds.dts)?
What about pq3-i2c-*.dtsi?
-Scott
--
To unsubscribe from this list: send the line "unsubscribe linux-i2c" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
