提交 69de52ba 编写于 作者: D Dirk Behme 提交者: Linus Walleij

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

With commit 39b2bbe3 ("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: NDirk Behme <dirk.behme@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
上级 e20538b8
......@@ -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.
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