| Devices |
| ======= |
| |
| Device bindings are described by their own individual binding files. |
| |
| U-Boot provides for some optional properties which are documented here. See |
| also hid-over-i2c.txt which describes HID devices. See also |
| Documentation/firmware-guide/acpi/enumeration.rst in the Linux kernel for |
| the acpi,compatible property. |
| |
| - acpi,has-power-resource : (boolean) true if this device has a power resource. |
| This causes an ACPI PowerResource to be written containing the properties |
| provided by this binding, to describe how to handle powering the device up |
| and down using GPIOs |
| - acpi,compatible : compatible string to report |
| - acpi,ddn : Contains the string to use as the _DDN (DOS (Disk Operating |
| System) Device Name) |
| - acpi,hid : Contains the string to use as the HID (Hardware ID) |
| identifier _HID |
| - acpi,uid : _UID value for device |
| - linux,probed : Tells U-Boot to add 'linux,probed' to the ACPI tables so that |
| Linux will only load the driver if the device can be detected (e.g. on I2C |
| bus). Note that this is an out-of-tree Linux feature. |
| |
| |
| Example |
| ------- |
| |
| elan_touchscreen: elan-touchscreen@10 { |
| compatible = "i2c-chip"; |
| reg = <0x10>; |
| acpi,hid = "ELAN0001"; |
| acpi,ddn = "ELAN Touchscreen"; |
| interrupts-extended = <&acpi_gpe GPIO_21_IRQ IRQ_TYPE_EDGE_FALLING>; |
| linux,probed; |
| }; |