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-rw-r--r--Documentation/powerpc/booting-without-of.txt42
1 files changed, 42 insertions, 0 deletions
diff --git a/Documentation/powerpc/booting-without-of.txt b/Documentation/powerpc/booting-without-of.txt
index b68684d39f9..f6394b50943 100644
--- a/Documentation/powerpc/booting-without-of.txt
+++ b/Documentation/powerpc/booting-without-of.txt
@@ -2160,6 +2160,48 @@ platforms are moved over to use the flattened-device-tree model.
};
};
+ x) 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.
+ - clock-frequency : Can be used to set the i2c clock frequency. If
+ unspecified, a default frequency of 60kHz is being used.
+ The following two properties are deprecated. They are only used by legacy
+ i2c drivers to find the bus to probe:
+ - linux,i2c-index : Can be used to hard code an i2c bus number. By default,
+ the bus number is dynamically assigned by the i2c core.
+ - linux,i2c-class : Can be used to override the i2c class. The class is used
+ by legacy 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
+
+ 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: