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Documentation: gpio: board: add flags parameter to gpiod_get*() functions

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With commit 39b2bbe3d7 ("gpio: add flags argument to gpiod_get*()
functions") the gpiod_get*() functions got a 'flags' parameter. Reflect
this in the documentation, too.

Signed-off-by: Dirk Behme <dirk.behme@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This commit is contained in:
Dirk Behme 2015-09-02 20:07:09 +02:00 committed by Linus Walleij
parent e20538b82f
commit 69de52ba32
1 changed files with 13 additions and 12 deletions
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25
Documentation/gpio/board.txt
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@ -39,11 +39,11 @@ This property will make GPIOs 15, 16 and 17 available to the driver under the
struct gpio_desc *red, *green, *blue, *power;
red = gpiod_get_index(dev, "led", 0);
green = gpiod_get_index(dev, "led", 1);
blue = gpiod_get_index(dev, "led", 2);
red = gpiod_get_index(dev, "led", 0, GPIOD_OUT_HIGH);
green = gpiod_get_index(dev, "led", 1, GPIOD_OUT_HIGH);
blue = gpiod_get_index(dev, "led", 2, GPIOD_OUT_HIGH);
power = gpiod_get(dev, "power");
power = gpiod_get(dev, "power", GPIOD_OUT_HIGH);
The led GPIOs will be active-high, while the power GPIO will be active-low (i.e.
gpiod_is_active_low(power) will be true).
@ -142,13 +142,14 @@ The driver controlling "foo.0" will then be able to obtain its GPIOs as follows:
struct gpio_desc *red, *green, *blue, *power;
red = gpiod_get_index(dev, "led", 0);
green = gpiod_get_index(dev, "led", 1);
blue = gpiod_get_index(dev, "led", 2);
red = gpiod_get_index(dev, "led", 0, GPIOD_OUT_HIGH);
green = gpiod_get_index(dev, "led", 1, GPIOD_OUT_HIGH);
blue = gpiod_get_index(dev, "led", 2, GPIOD_OUT_HIGH);
power = gpiod_get(dev, "power");
gpiod_direction_output(power, 1);
power = gpiod_get(dev, "power", GPIOD_OUT_HIGH);
Since the "power" GPIO 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.
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.