1*4882a593SmuzhiyunDevice-tree bindings for I2C OPAL driver 2*4882a593Smuzhiyun---------------------------------------- 3*4882a593Smuzhiyun 4*4882a593SmuzhiyunMost of the device node and properties layout is specific to the firmware and 5*4882a593Smuzhiyunused by the firmware itself for configuring the port. From the linux 6*4882a593Smuzhiyunperspective, the properties of use are "ibm,port-name" and "ibm,opal-id". 7*4882a593Smuzhiyun 8*4882a593SmuzhiyunRequired properties: 9*4882a593Smuzhiyun 10*4882a593Smuzhiyun- reg: Port-id within a given master 11*4882a593Smuzhiyun- compatible: must be "ibm,opal-i2c" 12*4882a593Smuzhiyun- ibm,opal-id: Refers to a specific bus and used to identify it when calling 13*4882a593Smuzhiyun the relevant OPAL functions. 14*4882a593Smuzhiyun- bus-frequency: Operating frequency of the i2c bus (in HZ). Informational for 15*4882a593Smuzhiyun linux, used by the FW though. 16*4882a593Smuzhiyun 17*4882a593SmuzhiyunOptional properties: 18*4882a593Smuzhiyun- ibm,port-name: Firmware provides this name that uniquely identifies the i2c 19*4882a593Smuzhiyun port. 20*4882a593Smuzhiyun 21*4882a593SmuzhiyunThe node contains a number of other properties that are used by the FW itself 22*4882a593Smuzhiyunand depend on the specific hardware implementation. The example below depicts 23*4882a593Smuzhiyuna P8 on-chip bus. 24*4882a593Smuzhiyun 25*4882a593SmuzhiyunExample: 26*4882a593Smuzhiyun 27*4882a593Smuzhiyuni2c-bus@0 { 28*4882a593Smuzhiyun reg = <0x0>; 29*4882a593Smuzhiyun bus-frequency = <0x61a80>; 30*4882a593Smuzhiyun compatible = "ibm,power8-i2c-port", "ibm,opal-i2c"; 31*4882a593Smuzhiyun ibm,opal-id = <0x1>; 32*4882a593Smuzhiyun ibm,port-name = "p8_00000000_e1p0"; 33*4882a593Smuzhiyun #address-cells = <0x1>; 34*4882a593Smuzhiyun phandle = <0x10000006>; 35*4882a593Smuzhiyun #size-cells = <0x0>; 36*4882a593Smuzhiyun linux,phandle = <0x10000006>; 37*4882a593Smuzhiyun}; 38