From mboxrd@z Thu Jan 1 00:00:00 1970 From: t.figa@samsung.com (Tomasz Figa) Date: Wed, 16 Jul 2014 14:34:59 +0200 Subject: [PATCH 2/2] ARM: dts: ODROID i2c improvements In-Reply-To: <1405500606-5752-2-git-send-email-drake@endlessm.com> References: <1405500606-5752-1-git-send-email-drake@endlessm.com> <1405500606-5752-2-git-send-email-drake@endlessm.com> Message-ID: <53C67173.9060006@samsung.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 16.07.2014 10:50, Daniel Drake wrote: > 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 { > Reviewed-by: Tomasz Figa -- Best regards, Tomasz