| * HID over I2C Device-Tree bindings |
| |
| HID over I2C provides support for various Human Interface Devices over the |
| I2C bus. These devices can be for example touchpads, keyboards, touch screens |
| or sensors. |
| |
| The specification has been written by Microsoft and is currently available here: |
| http://msdn.microsoft.com/en-us/library/windows/hardware/hh852380.aspx |
| |
| If this binding is used, the kernel module i2c-hid will handle the communication |
| with the device and the generic hid core layer will handle the protocol. |
| |
| Required properties: |
| - compatible: must be "hid-over-i2c" |
| - reg: i2c slave address |
| - hid-descr-addr: HID descriptor address |
| - interrupts: interrupt line |
| |
| Additional optional properties: |
| |
| Some devices may support additional optional properties to help with, e.g., |
| power sequencing. The following properties can be supported by one or more |
| device-specific compatible properties, which should be used in addition to the |
| "hid-over-i2c" string. |
| |
| - compatible: |
| * "wacom,w9013" (Wacom W9013 digitizer). Supports: |
| - vdd-supply (3.3V) |
| - vddl-supply (1.8V) |
| - post-power-on-delay-ms |
| |
| - vdd-supply: phandle of the regulator that provides the supply voltage. |
| - post-power-on-delay-ms: time required by the device after enabling its regulators |
| or powering it on, before it is ready for communication. |
| - touchscreen-inverted-x: See touchscreen.txt |
| - touchscreen-inverted-y: See touchscreen.txt |
| |
| Example: |
| |
| i2c-hid-dev@2c { |
| compatible = "hid-over-i2c"; |
| reg = <0x2c>; |
| hid-descr-addr = <0x0020>; |
| interrupt-parent = <&gpx3>; |
| interrupts = <3 2>; |
| }; |