[PATCH RFC] dt-bindings: gpio: introduce hog properties with less ambiguity

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From: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx>

For active low lines the semantic of output-low and output-high is hard
to grasp because there is a double negation involved and so output-low
is actually a request to drive the line high (aka inactive).

So introduce output-inactive and output-active with the same semantic as
output-low and output-high have respectively today, but with a more
sensible name.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx>
---
Hello,

no code changes yet. Just asking for feedback if you consider this
sensible.

I don't like explaining that double inversion any more ...

Best regards
Uwe

 Documentation/devicetree/bindings/gpio/gpio.txt | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/Documentation/devicetree/bindings/gpio/gpio.txt b/Documentation/devicetree/bindings/gpio/gpio.txt
index a8895d339bfe..af2d3bd9412c 100644
--- a/Documentation/devicetree/bindings/gpio/gpio.txt
+++ b/Documentation/devicetree/bindings/gpio/gpio.txt
@@ -196,11 +196,16 @@ Only one of the following properties scanned in the order shown below.
 This means that when multiple properties are present they will be searched
 in the order presented below and the first match is taken as the intended
 configuration.
-- input:      A property specifying to set the GPIO direction as input.
-- output-low  A property specifying to set the GPIO direction as output with
-	      the value low.
-- output-high A property specifying to set the GPIO direction as output with
-	      the value high.
+- input:            A property specifying to set the GPIO direction as input.
+- output-inactive:  A property specifying to set the GPIO direction as output with
+		    the inactive value (depending on the line's polarity, which
+		    is active-high by default)
+- output-active:    A property specifying to set the GPIO direction as output with
+		    the active value.
+
+For backwards compatibility "output-low" and "output-high" should be supported
+as aliases for "output-inactive" and "output-active" respectively. Their usage is
+misleading for active-low outputs, so their use is discouraged.
 
 Optional properties:
 - line-name:  The GPIO label name. If not present the node name is used.
-- 
2.27.0




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