From mboxrd@z Thu Jan 1 00:00:00 1970 From: drake@endlessm.com (Daniel Drake) Date: Wed, 16 Jul 2014 09:50:06 +0100 Subject: [PATCH 2/2] ARM: dts: ODROID i2c improvements In-Reply-To: <1405500606-5752-1-git-send-email-drake@endlessm.com> References: <1405500606-5752-1-git-send-email-drake@endlessm.com> Message-ID: <1405500606-5752-2-git-send-email-drake@endlessm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org 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 --- 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