From mboxrd@z Thu Jan 1 00:00:00 1970 From: dianders@chromium.org (Doug Anderson) Date: Thu, 14 Feb 2013 16:21:16 -0800 Subject: [PATCH v2 2/3] ARM: dts: Add i2c-arbitrator bus for exynos5250-snow In-Reply-To: <1360887677-20758-1-git-send-email-dianders@chromium.org> References: <1360887677-20758-1-git-send-email-dianders@chromium.org> Message-ID: <1360887677-20758-2-git-send-email-dianders@chromium.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org We need to use the i2c-arbitrator to talk to any of the devices on i2c bus 4 on exynos5250-snow so that we don't confuse the embedded controller (EC). Add the i2c-arbitrator to the device tree. As we add future devices (keyboard, sbs, tps65090) we'll add them on top of this. The arbitrated bus is numbered 104 simply as a convenience to make it easier for people poking around to guess that it might have something to do with the physical bus 4. The addition is split between the cros5250-common and the snow device tree file since not all cros5250-class devices use arbitration. Signed-off-by: Doug Anderson --- Changes in v2: - Use new device tree property names / compatible string. - Include that the GPIOs for arbitration are active low. arch/arm/boot/dts/cros5250-common.dtsi | 5 ++++- arch/arm/boot/dts/exynos5250-snow.dts | 25 +++++++++++++++++++++++++ 2 files changed, 29 insertions(+), 1 deletion(-) diff --git a/arch/arm/boot/dts/cros5250-common.dtsi b/arch/arm/boot/dts/cros5250-common.dtsi index 46c0980..f451375 100644 --- a/arch/arm/boot/dts/cros5250-common.dtsi +++ b/arch/arm/boot/dts/cros5250-common.dtsi @@ -58,7 +58,10 @@ }; i2c at 12CA0000 { - status = "disabled"; + samsung,i2c-sda-delay = <100>; + samsung,i2c-max-bus-freq = <66000>; + gpios = <&gpa2 0 3 3 0>, + <&gpa2 1 3 3 0>; }; i2c at 12CB0000 { diff --git a/arch/arm/boot/dts/exynos5250-snow.dts b/arch/arm/boot/dts/exynos5250-snow.dts index 17dd951..d2d4b48 100644 --- a/arch/arm/boot/dts/exynos5250-snow.dts +++ b/arch/arm/boot/dts/exynos5250-snow.dts @@ -16,6 +16,10 @@ model = "Google Snow"; compatible = "google,snow", "samsung,exynos5250"; + aliases { + i2c104 = &i2c_104; + }; + gpio-keys { compatible = "gpio-keys"; @@ -29,6 +33,27 @@ }; }; + i2c-arbitrator { + compatible = "i2c-arbitrator-cros-ec"; + #address-cells = <1>; + #size-cells = <0>; + + i2c-parent = <&{/i2c@12CA0000}>; + + ap-claim-gpio = <&gpf0 3 1 0x10000 0>; + ec-claim-gpio = <&gpe0 4 0 0x10003 0>; + slew-delay-us = <10>; + wait-retry-us = <3000>; + wait-free-us = <50000>; + + /* Use ID 104 as a hint that we're on physical bus 4 */ + i2c_104: i2c at 0 { + reg = <0>; + #address-cells = <1>; + #size-cells = <0>; + }; + }; + /* * On Snow we've got SIP WiFi and so can keep drive strengths low to * reduce EMI. -- 1.8.1