38 lines
1.2 KiB
Plaintext
38 lines
1.2 KiB
Plaintext
Device-tree bindings for I2C OPAL driver
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Most of the device node and properties layout is specific to the firmware and
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used by the firmware itself for configuring the port. From the linux
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perspective, the properties of use are "ibm,port-name" and "ibm,opal-id".
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Required properties:
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- reg: Port-id within a given master
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- compatible: must be "ibm,opal-i2c"
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- ibm,opal-id: Refers to a specific bus and used to identify it when calling
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the relevant OPAL functions.
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- bus-frequency: Operating frequency of the i2c bus (in HZ). Informational for
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linux, used by the FW though.
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Optional properties:
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- ibm,port-name: Firmware provides this name that uniquely identifies the i2c
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port.
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The node contains a number of other properties that are used by the FW itself
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and depend on the specific hardware implementation. The example below depicts
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a P8 on-chip bus.
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Example:
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i2c-bus@0 {
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reg = <0x0>;
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bus-frequency = <0x61a80>;
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compatible = "ibm,power8-i2c-port", "ibm,opal-i2c";
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ibm,opal-id = <0x1>;
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ibm,port-name = "p8_00000000_e1p0";
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#address-cells = <0x1>;
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phandle = <0x10000006>;
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#size-cells = <0x0>;
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linux,phandle = <0x10000006>;
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};
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