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Add i2c pins to dts and board setup

PATCH In review Jochen Friedrich 2 participants 3 messages May 21, 2008

Subsystems (5)
Device tree bindings Documentation PowerPC I2C subsystem host drivers +1 more subsystems
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Jochen Friedrich

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#0 lore raw

PATCH 1/1 Add i2c pins to dts and board setup

Initialize I2C pins on boards with CPM1/CPM2 controllers.

Signed-off-by Jochen Friedrich <[email protected]>
---
 Documentation/powerpc/booting-without-of.txt |   39 ++++++++++++++++++++++++++
 arch/powerpc/boot/dts/mpc8272ads.dts         |   11 +++++++
 arch/powerpc/boot/dts/mpc866ads.dts          |   11 +++++++
 arch/powerpc/boot/dts/mpc885ads.dts          |   11 +++++++
 arch/powerpc/platforms/82xx/mpc8272_ads.c    |    4 ++
 arch/powerpc/platforms/8xx/mpc86xads_setup.c |    4 ++
 arch/powerpc/platforms/8xx/mpc885ads_setup.c |    3 ++
 7 files changed, 83 insertions(+), 0 deletions(-)
Documentation/powerpc/booting-without-of.txt +39 -0
index 1d2a772..3fc4eb2 100644
@@ -2132,6 +2132,45 @@ platforms are moved over to use the flattened-device-tree model.
 		};
 	};
 
+   ix) I2C
+
+   The I2C controller is expressed as a bus under the CPM node.
+
+   Properties:
+   - compatible : "fsl,cpm1-i2c", "fsl,cpm2-i2c"
+   - reg : On CPM2 devices, the second resource doesn't specify the I2C
+     Parameter RAM itself, but the I2C_BASE field of the CPM2 Parameter RAM
+     (typically 0x8afc 0x2).
+   - #address-cells : Should be one. The cell is the i2c device address with
+     the r/w bit set to zero.
+   - #size-cells : Should be zero.
+   - linux,i2c-index : Can be used to hard code an i2c bus nummer.
+   - linux,i2c-class : Can be used to override the i2c class. The class is used
+     by old style i2c device drivers to find a bus in a specific context like
+     system management, video or sound. By default, I2C_CLASS_HWMON (1) is
+     being used. The definition of the classes can be found in
+     include/i2c/i2c.h
+   - bus-frequency : Can be used to set the i2c bus frequency. If unspecified,
+     a default frequency of 60kHz is being used.
+
+   Example, based on mpc823:
+
+	i2c@860 {
+		compatible = "fsl,mpc823-i2c",
+			     "fsl,cpm1-i2c";
+		reg = <0x860 0x20 0x3c80 0x30>;
+		interrupts = <16>;
+		interrupt-parent = <&CPM_PIC>;
+		fsl,cpm-command = <0x10>;
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		rtc@68 {
+			compatible = "dallas,ds1307";
+			reg = <0x68>;
+		};
+	};
+
    m) Chipselect/Local Bus
 
    Properties:
arch/powerpc/boot/dts/mpc8272ads.dts +11 -0
index 46e2da3..d27f8a7 100644
@@ -217,6 +217,17 @@
 				linux,network-index = <1>;
 				fsl,cpm-command = <0x16200300>;
 			};
+
+			i2c@11860 {
+				compatible = "fsl,mpc8272-i2c",
+					     "fsl,cpm2-i2c";
+				reg = <0x11860 0x20 0x8afc 0x2>;
+				interrupts = <1 8>;
+				interrupt-parent = <&PIC>;
+				fsl,cpm-command = <0x29600000>;
+				#address-cells = <1>;
+				#size-cells = <0>;
+			};
 		};
 
 		PIC: interrupt-controller@10c00 {
arch/powerpc/boot/dts/mpc866ads.dts +11 -0
index 765e43c..bd70065 100644
@@ -171,6 +171,17 @@
 				fsl,cpm-command = <0000>;
 				linux,network-index = <1>;
 			};
+
+			i2c@860 {
+				compatible = "fsl,mpc866-i2c",
+					     "fsl,cpm1-i2c";
+				reg = <0x860 0x20 0x3c80 0x30>;
+				interrupts = <16>;
+				interrupt-parent = <&CPM_PIC>;
+				fsl,cpm-command = <0x10>;
+				#address-cells = <1>;
+				#size-cells = <0>;
+			};
 		};
 	};
arch/powerpc/boot/dts/mpc885ads.dts +11 -0
index 9895043..b123e9f 100644
@@ -215,6 +215,17 @@
 				fsl,cpm-command = <0x80>;
 				linux,network-index = <2>;
 			};
+
+			i2c@860 {
+				compatible = "fsl,mpc885-i2c",
+					     "fsl,cpm1-i2c";
+				reg = <0x860 0x20 0x3c80 0x30>;
+				interrupts = <16>;
+				interrupt-parent = <&CPM_PIC>;
+				fsl,cpm-command = <0x10>;
+				#address-cells = <1>;
+				#size-cells = <0>;
+			};
 		};
 	};
arch/powerpc/platforms/82xx/mpc8272_ads.c +4 -0
index 7d30187..8054c68 100644
@@ -96,6 +96,10 @@ static struct cpm_pin mpc8272_ads_pins[] = {
 	{1, 31, CPM_PIN_OUTPUT | CPM_PIN_PRIMARY},
 	{2, 16, CPM_PIN_INPUT | CPM_PIN_PRIMARY},
 	{2, 17, CPM_PIN_INPUT | CPM_PIN_PRIMARY},
+
+	/* I2C */
+	{3, 14, CPM_PIN_INPUT | CPM_PIN_SECONDARY | CPM_PIN_OPENDRAIN},
+	{3, 15, CPM_PIN_INPUT | CPM_PIN_SECONDARY | CPM_PIN_OPENDRAIN},
 };
 
 static void __init init_ioports(void)
arch/powerpc/platforms/8xx/mpc86xads_setup.c +4 -0
index c028a5b..caaec29 100644
@@ -65,6 +65,10 @@ static struct cpm_pin mpc866ads_pins[] = {
 	{CPM_PORTD, 13, CPM_PIN_OUTPUT},
 	{CPM_PORTD, 14, CPM_PIN_OUTPUT},
 	{CPM_PORTD, 15, CPM_PIN_OUTPUT},
+
+	/* I2C */
+	{CPM_PORTB, 26, CPM_PIN_INPUT | CPM_PIN_OPENDRAIN},
+	{CPM_PORTB, 27, CPM_PIN_INPUT | CPM_PIN_OPENDRAIN},
 };
 
 static void __init init_ioports(void)
arch/powerpc/platforms/8xx/mpc885ads_setup.c +3 -0
index 6e7ded0..45ed6cd 100644
@@ -158,6 +158,9 @@ static struct cpm_pin mpc885ads_pins[] = {
 	{CPM_PORTE, 28, CPM_PIN_OUTPUT},
 	{CPM_PORTE, 29, CPM_PIN_OUTPUT},
 #endif
+	/* I2C */
+	{CPM_PORTB, 26, CPM_PIN_INPUT | CPM_PIN_OPENDRAIN},
+	{CPM_PORTB, 27, CPM_PIN_INPUT | CPM_PIN_OPENDRAIN},
 };
 
 static void __init init_ioports(void)
Signature · 1 line
1.5.5.1
#1 lore raw
Quoted 1 line · Jochen Friedrich

+ - linux,i2c-index : Can be used to hard code an i2c bus nummer.

s/nummer/number/

Why do we need this?

Documentation/powerpc/booting-without-of.txt platforms are moved over to use the flattened-device-tree model. · line 2152

Quoted 5 lines
Documentation/powerpc/booting-without-of.txt +5 -0
+   - linux,i2c-class : Can be used to override the i2c class. The class is used
+     by old style i2c device drivers to find a bus in a specific context like
+     system management, video or sound. By default, I2C_CLASS_HWMON (1) is
+     being used. The definition of the classes can be found in
+     include/i2c/i2c.h

It'd be better to just convert any needed old-style drivers than add this to the device tree.

Documentation/powerpc/booting-without-of.txt platforms are moved over to use the flattened-device-tree model. · line 2154

Quoted 2 lines
Documentation/powerpc/booting-without-of.txt +2 -0
+   - bus-frequency : Can be used to set the i2c bus frequency. If unspecified,
+     a default frequency of 60kHz is being used.

clock-frequency is the standard name for such things.

-Scott

author
#2 lore raw

Hi Scott,

Quoted 4 lines

Review

Quoted 2 lines
(quoted diff) +2 -0
+   - linux,i2c-index : Can be used to hard code an i2c bus number.
+   - linux,i2c-class : Can be used to override the i2c class.

Why do we need this?

There are still a bunch of i2c drivers using the old API (mainly v4l and dvb stuff) which are slowly being converted by their subsystem maintainers, though.

Quoted 2 lines

It'd be better to just convert any needed old-style drivers than add this to the device tree.

Sure. That's why the parameters are only optional. Once all i2c drivers are converted, these parameters won't be used anymore. Maybe they should be marked as deprecated.

Quoted 4 lines

Documentation/powerpc/booting-without-of.txt platforms are moved over to use the flattened-device-tree model. · line 2154

Quoted 2 lines
Documentation/powerpc/booting-without-of.txt +2 -0
+   - bus-frequency : Can be used to set the i2c bus frequency. If unspecified,
+     a default frequency of 60kHz is being used.

clock-frequency is the standard name for such things.

I was just confused by the fact that unlike a serial port, i2c is a bus itself.

Thanks,
Jochen