| 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>; |
| }; |
