exynos5: dt: Increase i2c-1 speed to as close as possible to 400kHz

A cyapa touchpad is attached to i2c-1, and it benefit from as fast an i2c
as possible (up to 400kHz).
In reality, the fastest freq this i2c hardware can acheive is 378 kHz.

Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
BUG=chrome-os-partner:10899
TEST=Boot and see the following bootup messages:
TEST="s3c-i2c s3c2440-i2c.1: bus frequency set to 378 KHz"
TEST=Also, ensure the cyapa driver is still loaded correctly, and that
TEST=talking to it is fast by reading back its firmware:
TEST=time cat /sys/kernel/debug/cyapa/1-0067/read_fw > /tmp/cyapa.fw

Change-Id: I7249c081f5f8aa48579c6c96043e2892ae2338ae
Reviewed-on: https://gerrit.chromium.org/gerrit/27757
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Benson Leung <bleung@chromium.org>
Reviewed-by: Daniel Kurtz <djkurtz@chromium.org>
Tested-by: Daniel Kurtz <djkurtz@chromium.org>
Commit-Ready: Daniel Kurtz <djkurtz@chromium.org>

diff --git a/arch/arm/boot/dts/cros5250-common.dtsi b/arch/arm/boot/dts/cros5250-common.dtsi
index e779e65..d260048 100644 (file)
--- a/arch/arm/boot/dts/cros5250-common.dtsi
+++ b/arch/arm/boot/dts/cros5250-common.dtsi
@@ -121,7 +121,7 @@
 
        i2c@12C70000 {
                samsung,i2c-sda-delay = <100>;
-               samsung,i2c-max-bus-freq = <66000>;
+               samsung,i2c-max-bus-freq = <400000>;
                gpios = <&gpb3 2 2 3 0>,
                        <&gpb3 3 2 3 0>;