ARM: mxs: Slow down the I2C clock speed

Slow down the I2C clock speed on M28 and SPS1 as it turns out the
I2C block in i.MX28 can not operate stable enough with the bus
running at 400kHz. Note that the driver used by Freescale runs
the bus at 250kHz when 400kHz speed is selected, but the mainline
Linux kernel runs the bus at actual 400kHz and that's where it is
occasionally unstable. Play safe and run the bus at 100kHz.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>

diff --git a/arch/arm/boot/dts/imx28-m28evk.dts b/arch/arm/boot/dts/imx28-m28evk.dts
index 6ce3d17c3a29c19c80ef6a04484fd59ec5e8765a..fd36e1cca1042306476c54d4038603780af358a1 100644 (file)
--- a/arch/arm/boot/dts/imx28-m28evk.dts
+++ b/arch/arm/boot/dts/imx28-m28evk.dts
@@ -152,7 +152,6 @@
                        i2c0: i2c@80058000 {
                                pinctrl-names = "default";
                                pinctrl-0 = <&i2c0_pins_a>;
-                               clock-frequency = <400000>;
                                status = "okay";
 
                                sgtl5000: codec@0a {

diff --git a/arch/arm/boot/dts/imx28-sps1.dts b/arch/arm/boot/dts/imx28-sps1.dts
index e6cde8aa7ffff5c3a2b670e2584c7475a8419525..6c6a5442800ad78adfe13ada4cf44a2cfd3cfbc5 100644 (file)
--- a/arch/arm/boot/dts/imx28-sps1.dts
+++ b/arch/arm/boot/dts/imx28-sps1.dts
@@ -70,7 +70,6 @@
                        i2c0: i2c@80058000 {
                                pinctrl-names = "default";
                                pinctrl-0 = <&i2c0_pins_a>;
-                               clock-frequency = <400000>;
                                status = "okay";
 
                                rtc: rtc@51 {