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

From: Alan Tull
Date: Wed Aug 08 2018 - 11:42:49 EST


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";
--
2.7.4