hwmon: (max6650) Add initial rpm target devicetree documentation
authorMike Looijmans <mike.looijmans@topic.nl>
Wed, 24 Aug 2016 08:13:27 +0000 (10:13 +0200)
committerGuenter Roeck <linux@roeck-us.net>
Fri, 9 Sep 2016 04:34:17 +0000 (21:34 -0700)
Add devicetree property for early initialization of the fan controller
to prevent overheating, for example when resetting the board while the
fan was completely turned off.

Signed-off-by: Mike Looijmans <mike.looijmans@topic.nl>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Documentation/devicetree/bindings/hwmon/max6650.txt

index d6c10e3680cb0de47226c98f132fa7561ca43e3a..f6bd87d8e284560bb5a3d141d6f7c4eda751edd9 100644 (file)
@@ -13,6 +13,10 @@ Optional properties, default is to retain the chip's current setting:
 - maxim,fan-prescale  : Pre-scaling value, as per datasheet [1]. Lower values
                        allow more fine-grained control of slower fans.
                        Valid: 1, 2, 4, 8, 16.
+- maxim,fan-target-rpm: Initial requested fan rotation speed. If specified, the
+                       driver selects closed-loop mode and the requested speed.
+                       This ensures the fan is already running before userspace
+                       takes over.
 
 Example:
        fan-max6650: max6650@1b {
@@ -20,4 +24,5 @@ Example:
                compatible = "maxim,max6650";
                maxim,fan-microvolt = <12000000>;
                maxim,fan-prescale = <4>;
+               maxim,fan-target-rpm = <1200>;
        };