hwmon: (gpio-fan) allow to use alarm support alone from DT

[firefly-linux-kernel-4.4.55.git] / Documentation / devicetree / bindings / gpio / gpio-fan.txt

diff --git a/Documentation/devicetree/bindings/gpio/gpio-fan.txt b/Documentation/devicetree/bindings/gpio/gpio-fan.txt
index 2dd457a3469af94baa89534c79aaacdf56e2d75e..f996d428f1323d65af6f20720ba33aa12020706c 100644 (file)
--- a/Documentation/devicetree/bindings/gpio/gpio-fan.txt
+++ b/Documentation/devicetree/bindings/gpio/gpio-fan.txt
@@ -2,16 +2,18 @@ Bindings for fan connected to GPIO lines
 
 Required properties:
 - compatible : "gpio-fan"
+
+Optional properties:
 - gpios: Specifies the pins that map to bits in the control value,
   ordered MSB-->LSB.
 - gpio-fan,speed-map: A mapping of possible fan RPM speeds and the
   control value that should be set to achieve them. This array
   must have the RPM values in ascending order.
-
-Optional properties:
 - alarm-gpios: This pin going active indicates something is wrong with
   the fan, and a udev event will be fired.
 
+Note: At least one the "gpios" or "alarm-gpios" properties must be set.
+
 Examples:
 
        gpio_fan {