1* HID over I2C Device-Tree bindings 2 3HID over I2C provides support for various Human Interface Devices over the 4I2C bus. These devices can be for example touchpads, keyboards, touch screens 5or sensors. 6 7The specification has been written by Microsoft and is currently available here: 8http://msdn.microsoft.com/en-us/library/windows/hardware/hh852380.aspx 9 10If this binding is used, the kernel module i2c-hid will handle the communication 11with the device and the generic hid core layer will handle the protocol. 12 13Required properties: 14- compatible: must be "hid-over-i2c" 15- reg: i2c slave address 16- hid-descr-addr: HID descriptor address 17- interrupts: interrupt line 18 19Additional optional properties: 20 21Some devices may support additional optional properties to help with, e.g., 22power sequencing. The following properties can be supported by one or more 23device-specific compatible properties, which should be used in addition to the 24"hid-over-i2c" string. 25 26- compatible: 27 * "wacom,w9013" (Wacom W9013 digitizer). Supports: 28 - vdd-supply (3.3V) 29 - vddl-supply (1.8V) 30 - post-power-on-delay-ms 31 32- vdd-supply: phandle of the regulator that provides the supply voltage. 33- post-power-on-delay-ms: time required by the device after enabling its regulators 34 or powering it on, before it is ready for communication. 35 36Example: 37 38 i2c-hid-dev@2c { 39 compatible = "hid-over-i2c"; 40 reg = <0x2c>; 41 hid-descr-addr = <0x0020>; 42 interrupt-parent = <&gpx3>; 43 interrupts = <3 2>; 44 }; 45