1*c66ec88fSEmmanuel VadotDevice-tree bindings for I2C OPAL driver 2*c66ec88fSEmmanuel Vadot---------------------------------------- 3*c66ec88fSEmmanuel Vadot 4*c66ec88fSEmmanuel VadotMost of the device node and properties layout is specific to the firmware and 5*c66ec88fSEmmanuel Vadotused by the firmware itself for configuring the port. From the linux 6*c66ec88fSEmmanuel Vadotperspective, the properties of use are "ibm,port-name" and "ibm,opal-id". 7*c66ec88fSEmmanuel Vadot 8*c66ec88fSEmmanuel VadotRequired properties: 9*c66ec88fSEmmanuel Vadot 10*c66ec88fSEmmanuel Vadot- reg: Port-id within a given master 11*c66ec88fSEmmanuel Vadot- compatible: must be "ibm,opal-i2c" 12*c66ec88fSEmmanuel Vadot- ibm,opal-id: Refers to a specific bus and used to identify it when calling 13*c66ec88fSEmmanuel Vadot the relevant OPAL functions. 14*c66ec88fSEmmanuel Vadot- bus-frequency: Operating frequency of the i2c bus (in HZ). Informational for 15*c66ec88fSEmmanuel Vadot linux, used by the FW though. 16*c66ec88fSEmmanuel Vadot 17*c66ec88fSEmmanuel VadotOptional properties: 18*c66ec88fSEmmanuel Vadot- ibm,port-name: Firmware provides this name that uniquely identifies the i2c 19*c66ec88fSEmmanuel Vadot port. 20*c66ec88fSEmmanuel Vadot 21*c66ec88fSEmmanuel VadotThe node contains a number of other properties that are used by the FW itself 22*c66ec88fSEmmanuel Vadotand depend on the specific hardware implementation. The example below depicts 23*c66ec88fSEmmanuel Vadota P8 on-chip bus. 24*c66ec88fSEmmanuel Vadot 25*c66ec88fSEmmanuel VadotExample: 26*c66ec88fSEmmanuel Vadot 27*c66ec88fSEmmanuel Vadoti2c-bus@0 { 28*c66ec88fSEmmanuel Vadot reg = <0x0>; 29*c66ec88fSEmmanuel Vadot bus-frequency = <0x61a80>; 30*c66ec88fSEmmanuel Vadot compatible = "ibm,power8-i2c-port", "ibm,opal-i2c"; 31*c66ec88fSEmmanuel Vadot ibm,opal-id = <0x1>; 32*c66ec88fSEmmanuel Vadot ibm,port-name = "p8_00000000_e1p0"; 33*c66ec88fSEmmanuel Vadot #address-cells = <0x1>; 34*c66ec88fSEmmanuel Vadot phandle = <0x10000006>; 35*c66ec88fSEmmanuel Vadot #size-cells = <0x0>; 36*c66ec88fSEmmanuel Vadot linux,phandle = <0x10000006>; 37*c66ec88fSEmmanuel Vadot}; 38