Documentation/devicetree/bindings/i2c/i2c-opal.txt

   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 };