Devices need to report various identifiers in the ACPI tables. Rather than
hard-coding these in drivers it is typically better to put them in the
device tree.
Add a binding file to describe this.
Signed-off-by: Simon Glass <s...@chromium.org>
---
doc/device-tree-bindings/device.txt | 37 +++++++++++++++++++++++++++++
1 file changed, 37 insertions(+)
create mode 100644 doc/device-tree-bindings/device.txt
diff --git a/doc/device-tree-bindings/device.txt
b/doc/device-tree-bindings/device.txt
new file mode 100644
index 0000000000..e625e67f43
--- /dev/null
+++ b/doc/device-tree-bindings/device.txt
@@ -0,0 +1,37 @@
+Devices
+=======
+
+Device bindings are described by their own individual binding files.
+
+U-Boot provides for some optional properties which are documented here.
+
+ - acpi,has-power-resource : (boolean) true if this device has a power
resource.
+ This causes a PRIC (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,cid : Contains the string to use as the compatible ID (_CID)
+ - acpi,compatible : compatible string to report
+ - acpi,desc : Contains the string to use as the _DDN (DOS (Disk Operating
+ System) Device Name)
+ - acpi,hid : Contains the string to use as the HID (Human Interface Device)
+ identifier _HID
+ - acpi,hid-desc-reg-offset : HID register offset (for Human Interface Devices)
+ - acpi,probed : Tells U-Boot to add 'linux,probed' to the ACPI tables so that
+ Linux will not re-init the device
+ - acpi,uid : _UID value for device
+
+
+Example
+-------
+
+synaptics_touchpad: synaptics-touchpad@2c {
+ compatible = "i2c-chip";
+ reg = <0x2c>;
+ acpi,hid = "PNP0C50";
+ acpi,cid = "PNP0C50";
+ acpi,desc = "Synaptics Touchpad";
+ interrupts-extended = <&acpi_gpe GPIO_18_IRQ
+ IRQ_TYPE_EDGE_FALLING>;
+ acpi,probed;
+ acpi,hid-desc-reg-offset = <0x20>;
+};
--
2.25.0.341.g760bfbb309-goog
