From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tomasz Figa Subject: Re: [PATCH 2/2] ARM: dts: ODROID i2c improvements Date: Wed, 16 Jul 2014 14:34:59 +0200 Message-ID: <53C67173.9060006@samsung.com> References: <1405500606-5752-1-git-send-email-drake@endlessm.com> <1405500606-5752-2-git-send-email-drake@endlessm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from mailout1.w1.samsung.com ([210.118.77.11]:40661 "EHLO mailout1.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755112AbaGPMfi (ORCPT ); Wed, 16 Jul 2014 08:35:38 -0400 Received: from eucpsbgm1.samsung.com (unknown [203.254.199.244]) by mailout1.w1.samsung.com (Oracle Communications Messaging Server 7u4-24.01(7.0.4.24.0) 64bit (built Nov 17 2011)) with ESMTP id <0N8T006J21N7GEB0@mailout1.w1.samsung.com> for linux-samsung-soc@vger.kernel.org; Wed, 16 Jul 2014 13:35:31 +0100 (BST) In-reply-to: <1405500606-5752-2-git-send-email-drake@endlessm.com> Sender: linux-samsung-soc-owner@vger.kernel.org List-Id: linux-samsung-soc@vger.kernel.org To: Daniel Drake , kgene.kim@samsung.com Cc: linux-samsung-soc@vger.kernel.org, liquid.acid@gmx.net, m.szyprowski@samsung.com, 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@13860000 { > pinctrl-0 = <&i2c0_bus>; > pinctrl-names = "default"; > + samsung,i2c-sda-delay = <100>; > + samsung,i2c-max-bus-freq = <400000>; > status = "okay"; > > usb3503: usb3503@08 { > Reviewed-by: Tomasz Figa -- Best regards, Tomasz 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