Most of the LEDs are powered by a voltage/current regulator. Describing it
in the device-tree makes it possible for the LED core to enable/disable it
when needed.
Cc: devicetree@xxxxxxxxxxxxxxx
To: robh+dt@xxxxxxxxxx
To: mark.rutland@xxxxxxx
Signed-off-by: Jean-Jacques Hiblot <jjhiblot@xxxxxx>
---
Documentation/devicetree/bindings/leds/common.txt | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/Documentation/devicetree/bindings/leds/common.txt b/Documentation/devicetree/bindings/leds/common.txt
index 6d44f0c38487..dacaf863d687 100644
--- a/Documentation/devicetree/bindings/leds/common.txt
+++ b/Documentation/devicetree/bindings/leds/common.txt
@@ -96,6 +96,19 @@ Optional properties for child nodes:
- panic-indicator : This property specifies that the LED should be used,
if at all possible, as a panic indicator.
+- power-supply : A voltage/current regulator used to to power the LED. When a
+ LED is turned off, the LED core disable its regulator. The
+ same regulator can power many LED (or other) devices. It is
+ turned off only when all of its users disabled it.
+
+- power-off-delays-ms: This property specifies the delay between the time a LED
+ is turned off and the time the regulator is turned off.
+ It can be used to limit the overhead of the regulator
+ handling if the LED is toggling fast.
+ ex: if power-off-delays-ms is set to 500 ms, the
+ regulator will not be turned off until the LED is turned
+ off for more than 500ms.
+
- trigger-sources : List of devices which should be used as a source triggering
this LED activity. Some LEDs can be related to a specific
device and should somehow indicate its state. E.g. USB 2.0
@@ -143,6 +156,7 @@ led-controller@0 {
function = LED_FUNCTION_STATUS;
linux,default-trigger = "heartbeat";
gpios = <&gpio0 0 GPIO_ACTIVE_HIGH>;
+ power-supply = <&led_regulator>;
};
led1 {
--
2.17.1
