Documentation: Add examples to samsung-pinctrl device tree bindings documentation

This patch adds examples to samsung-pinctrl.txt documentaion file
on how to make gpio binding and gpio request

Signed-off-by: Leela Krishna Amudala <l.krishna@samsung.com>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Tomasz Figa <t.figa@samsung.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
This commit is contained in:
Leela Krishna Amudala 2013-06-18 06:58:48 +09:00 committed by Kukjin Kim
parent de39310ddf
commit c91f2a03cf

View File

@ -21,8 +21,18 @@ Required Properties:
- gpio-controller: identifies the node as a gpio controller and pin bank.
- #gpio-cells: number of cells in GPIO specifier. Since the generic GPIO
binding is used, the amount of cells must be specified as 2. See generic
GPIO binding documentation for description of particular cells.
binding is used, the amount of cells must be specified as 2. See the below
mentioned gpio binding representation for description of particular cells.
Eg: <&gpx2 6 0>
<[phandle of the gpio controller node]
[pin number within the gpio controller]
[flags]>
Values for gpio specifier:
- Pin number: is a value between 0 to 7.
- Flags: 0 - Active High
1 - Active Low
- Pin mux/config groups as child nodes: The pin mux (selecting pin function
mode) and pin config (pull up/down, driver strength) settings are represented
@ -266,3 +276,33 @@ Example 4: Set up the default pin state for uart controller.
pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
}
Example 5: A display port client node that supports 'default' pinctrl state
and gpio binding.
display-port-controller {
/* ... */
samsung,hpd-gpio = <&gpx2 6 0>;
pinctrl-names = "default";
pinctrl-0 = <&dp_hpd>;
};
Example 6: Request the gpio for display port controller
static int exynos_dp_probe(struct platform_device *pdev)
{
int hpd_gpio, ret;
struct device *dev = &pdev->dev;
struct device_node *dp_node = dev->of_node;
/* ... */
hpd_gpio = of_get_named_gpio(dp_node, "samsung,hpd-gpio", 0);
/* ... */
ret = devm_gpio_request_one(&pdev->dev, hpd_gpio, GPIOF_IN,
"hpd_gpio");
/* ... */
}