Re: [PATCH] arm64: dts: stratix10: i2c clock running out of spec

From: Dinh Nguyen
Date: Wed Aug 15 2018 - 11:09:23 EST




On 08/08/2018 10:42 AM, Alan Tull wrote:
> DesignWare I2C controller was observed running at 105.93kHz rather
> than the specified 100kHz. Adjust device tree settings to bring it
> within spec (a slightly conservative 98 MHz).
>
> Signed-off-by: Alan Tull <atull@xxxxxxxxxx>
> ---
> arch/arm64/boot/dts/altera/socfpga_stratix10_socdk.dts | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/arch/arm64/boot/dts/altera/socfpga_stratix10_socdk.dts b/arch/arm64/boot/dts/altera/socfpga_stratix10_socdk.dts
> index 6edc4fa..53cf195 100644
> --- a/arch/arm64/boot/dts/altera/socfpga_stratix10_socdk.dts
> +++ b/arch/arm64/boot/dts/altera/socfpga_stratix10_socdk.dts
> @@ -124,6 +124,8 @@
> &i2c1 {
> status = "okay";
> clock-frequency = <100000>;
> + i2c-sda-falling-time-ns = <890>; /* hcnt */
> + i2c-sdl-falling-time-ns = <890>; /* lcnt */
>
> adc@14 {
> compatible = "lltc,ltc2497";
>

Applied!

Thanks,
Dinh