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

Alexandre Belloni alexandre.belloni at free-electrons.com
Thu Apr 18 11:38:55 EDT 2013


From: Maxime Ripard <maxime.ripard at free-electrons.com>

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 at free-electrons.com>
---
 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 79a2007..a333dbf 100644
--- a/arch/arm/boot/dts/imx28-cfa10049.dts
+++ b/arch/arm/boot/dts/imx28-cfa10049.dts
@@ -138,6 +138,17 @@
 					fsl,voltage = <1>;
 					fsl,pull-up = <0>; /* 0 will enable the keeper */
 				};
+
+				i2c1_pins_cfa10049: i2c1 at 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>;
+				};
 			};
 
 			lcdif at 80030000 {
@@ -155,49 +166,6 @@
 				status = "okay";
 			};
 
-			i2c1: i2c at 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 at 0 {
-					reg = <0>;
-				};
-
-				i2c at 1 {
-					reg = <1>;
-				};
-
-				i2c at 2 {
-					reg = <2>;
-				};
-
-				i2c at 3 {
-					reg = <3>;
-					#address-cells = <1>;
-					#size-cells = <0>;
-
-					pca9555: pca9555 at 20 {
-						compatible = "nxp,pca9555";
-						interrupt-parent = <&gpio2>;
-						interrupts = <19 0x2>;
-						gpio-controller;
-						#gpio-cells = <2>;
-						interrupt-controller;
-						#interrupt-cells = <2>;
-						reg = <0x20>;
-					};
-				};
-			};
-
 			usbphy1: usbphy at 8007e000 {
 				status = "okay";
 			};
@@ -322,6 +290,60 @@
 		rotary-encoder,relative-axis;
 	};
 
+	i2c1gpio: i2c at 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 at 0 {
+			reg = <0>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+		};
+
+		i2c at 1 {
+			reg = <1>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+		};
+
+		i2c at 2 {
+			reg = <2>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+		};
+
+		i2c at 3 {
+			reg = <3>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			pca9555: pca9555 at 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>;
-- 
1.7.10.4




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