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

Daniel Drake drake at endlessm.com
Wed Jul 16 01:50:06 PDT 2014


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 {
-- 
1.9.1




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