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