On Fri, Nov 21, 2014 at 8:54 AM, Benoit Parrot <bparrot@xxxxxx> wrote: > Add GPIO hogging documentation to gpio.txt > > Signed-off-by: Benoit Parrot <bparrot@xxxxxx> > --- > Changes since v1: > * Split the devicetree bindings documentation in its own patch. > > Documentation/devicetree/bindings/gpio/gpio.txt | 25 +++++++++++++++++++++++++ > 1 file changed, 25 insertions(+) > > diff --git a/Documentation/devicetree/bindings/gpio/gpio.txt b/Documentation/devicetree/bindings/gpio/gpio.txt > index 3fb8f53..82755e2 100644 > --- a/Documentation/devicetree/bindings/gpio/gpio.txt > +++ b/Documentation/devicetree/bindings/gpio/gpio.txt > @@ -103,6 +103,24 @@ Every GPIO controller node must contain both an empty "gpio-controller" > property, and a #gpio-cells integer property, which indicates the number of > cells in a gpio-specifier. > > +The GPIO chip may contain GPIO hog definitions. GPIO hogging is a mechanism > +providing automatic GPIO request and configuration as part of the > +gpio-controller's driver probe function. > + > +Each GPIO hog definition is represented as a child node of the GPIO controller. > +Required properties: > +- gpio-hog: a property specifying that this child node represent a gpio-hog. > +- gpios: store the gpio information (id, flags, ...). Shall contain the > + number of cells specified in its parent node (GPIO controller node). > +- input: a property specifying to set the GPIO direction as input. > +- output-high: a property specifying to set the GPIO direction to output with > + the value high. > +- output-low: a property specifying to set the GPIO direction to output with > + the value low. > + > +Optional properties: > +- line-name: the GPIO label name. If not present the node name is used. > + > Example of two SOC GPIO banks defined as gpio-controller nodes: > > qe_pio_a: gpio-controller@1400 { > @@ -110,6 +128,13 @@ Example of two SOC GPIO banks defined as gpio-controller nodes: > reg = <0x1400 0x18>; > gpio-controller; > #gpio-cells = <2>; > + > + line_b: line_b { Mmm what is the label used for? Can this node ever be referenced from somewhere else? -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html