[PATCHv2 2/3] ARM: mxs: cfa10049: Switch bus i2c1 to bitbanging

From: Alexandre Belloni
Date: Thu Jun 20 2013 - 14:58:21 EST


From: Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx>

The ADCs connected to this bus have been experiencing some timeout
issues when using the iMX28 i2c controller. Switching back to bitbanging
solves this.

Signed-off-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxxxxxxxxx>
---
arch/arm/boot/dts/imx28-cfa10049.dts | 108 +++++++++++++++++++++--------------
1 file changed, 65 insertions(+), 43 deletions(-)

diff --git a/arch/arm/boot/dts/imx28-cfa10049.dts b/arch/arm/boot/dts/imx28-cfa10049.dts
index 05ae549..d3758c2 100644
--- a/arch/arm/boot/dts/imx28-cfa10049.dts
+++ b/arch/arm/boot/dts/imx28-cfa10049.dts
@@ -139,6 +139,17 @@
fsl,pull-up = <0>; /* 0 will enable the keeper */
};

+ i2c1_pins_cfa10049: i2c1@0 {
+ reg = <0>;
+ fsl,pinmux-ids = <
+ 0x3103 /* MX28_PAD_PWM0__GPIO */
+ 0x3113 /* MX28_PAD_PWM1__I2C1_SDA */
+ >;
+ fsl,drive-strength = <1>;
+ fsl,voltage = <1>;
+ fsl,pull-up = <1>;
+ };
+
fiq_pins_cfa10049: fiq@0 {
reg = <0>;
fsl,pinmux-ids = <
@@ -199,49 +210,6 @@
status = "okay";
};

- i2c1: i2c@8005a000 {
- pinctrl-names = "default";
- pinctrl-0 = <&i2c1_pins_a>;
- status = "okay";
- };
-
- i2cmux {
- compatible = "i2c-mux-gpio";
- #address-cells = <1>;
- #size-cells = <0>;
- mux-gpios = <&gpio1 22 0 &gpio1 23 0>;
- i2c-parent = <&i2c1>;
-
- i2c@0 {
- reg = <0>;
- };
-
- i2c@1 {
- reg = <1>;
- };
-
- i2c@2 {
- reg = <2>;
- };
-
- i2c@3 {
- reg = <3>;
- #address-cells = <1>;
- #size-cells = <0>;
-
- pca9555: pca9555@20 {
- compatible = "nxp,pca9555";
- interrupt-parent = <&gpio2>;
- interrupts = <19 0x2>;
- gpio-controller;
- #gpio-cells = <2>;
- interrupt-controller;
- #interrupt-cells = <2>;
- reg = <0x20>;
- };
- };
- };
-
usbphy1: usbphy@8007e000 {
status = "okay";
};
@@ -366,6 +334,60 @@
rotary-encoder,relative-axis;
};

+ i2c1gpio: i2c@0 {
+ compatible = "i2c-gpio";
+ pinctrl-0 = <&i2c1_pins_cfa10049>;
+ pinctrl-names = "default";
+ gpios = <
+ &gpio3 17 0 /* sda */
+ &gpio3 16 0 /* scl */
+ >;
+ i2c-gpio,delay-us = <2>; /* ~100 kHz */
+ };
+
+ i2cmux {
+ compatible = "i2c-mux-gpio";
+ #address-cells = <1>;
+ #size-cells = <0>;
+ mux-gpios = <&gpio1 22 0 &gpio1 23 0>;
+ i2c-parent = <&i2c1gpio>;
+
+ i2c@0 {
+ reg = <0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ };
+
+ i2c@1 {
+ reg = <1>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ };
+
+ i2c@2 {
+ reg = <2>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ };
+
+ i2c@3 {
+ reg = <3>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ pca9555: pca9555@20 {
+ compatible = "nxp,pca9555";
+ interrupt-parent = <&gpio2>;
+ interrupts = <19 0x2>;
+ gpio-controller;
+ #gpio-cells = <2>;
+ interrupt-controller;
+ #interrupt-cells = <2>;
+ reg = <0x20>;
+ };
+ };
+ };
+
backlight {
compatible = "pwm-backlight";
pwms = <&pwm 3 5000000>;
--
1.8.1.2

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