diff --git a/Documentation/gpio/board.txt b/Documentation/gpio/board.txt index 40884c4fe40c..a0f61898d493 100644 --- a/Documentation/gpio/board.txt +++ b/Documentation/gpio/board.txt @@ -6,7 +6,7 @@ Note that it only applies to the new descriptor-based interface. For a description of the deprecated integer-based GPIO interface please refer to gpio-legacy.txt (actually, there is no real mapping possible with the old interface; you just fetch an integer from somewhere and request the -corresponding GPIO. +corresponding GPIO). All platforms can enable the GPIO library, but if the platform strictly requires GPIO functionality to be present, it needs to select GPIOLIB from its @@ -162,6 +162,9 @@ The driver controlling "foo.0" will then be able to obtain its GPIOs as follows: Since the "led" GPIOs are mapped as active-high, this example will switch their signals to 1, i.e. enabling the LEDs. And for the "power" GPIO, which is mapped -as active-low, its actual signal will be 0 after this code. Contrary to the legacy -integer GPIO interface, the active-low property is handled during mapping and is -thus transparent to GPIO consumers. +as active-low, its actual signal will be 0 after this code. Contrary to the +legacy integer GPIO interface, the active-low property is handled during +mapping and is thus transparent to GPIO consumers. + +A set of functions such as gpiod_set_value() is available to work with +the new descriptor-oriented interface.