Commit | Line | Data |
---|---|---|
47083450 NG |
1 | Device-tree bindings for I2C OPAL driver |
2 | ---------------------------------------- | |
3 | ||
4 | Most of the device node and properties layout is specific to the firmware and | |
5 | used by the firmware itself for configuring the port. From the linux | |
6 | perspective, the properties of use are "ibm,port-name" and "ibm,opal-id". | |
7 | ||
8 | Required properties: | |
9 | ||
10 | - reg: Port-id within a given master | |
11 | - compatible: must be "ibm,opal-i2c" | |
12 | - ibm,opal-id: Refers to a specific bus and used to identify it when calling | |
13 | the relevant OPAL functions. | |
14 | - bus-frequency: Operating frequency of the i2c bus (in HZ). Informational for | |
15 | linux, used by the FW though. | |
16 | ||
17 | Optional properties: | |
18 | - ibm,port-name: Firmware provides this name that uniquely identifies the i2c | |
19 | port. | |
20 | ||
21 | The node contains a number of other properties that are used by the FW itself | |
22 | and depend on the specific hardware implementation. The example below depicts | |
23 | a P8 on-chip bus. | |
24 | ||
25 | Example: | |
26 | ||
27 | i2c-bus@0 { | |
28 | reg = <0x0>; | |
29 | bus-frequency = <0x61a80>; | |
30 | compatible = "ibm,power8-i2c-port", "ibm,opal-i2c"; | |
31 | ibm,opal-id = <0x1>; | |
32 | ibm,port-name = "p8_00000000_e1p0"; | |
33 | #address-cells = <0x1>; | |
34 | phandle = <0x10000006>; | |
35 | #size-cells = <0x0>; | |
36 | linux,phandle = <0x10000006>; | |
37 | }; |