Messages in this thread Patch in this message | | | From | David Daney <> | Subject | [PATCH] of/gpio: Define OF_GPIO_OPEN_DRAIN flag for Open Drain outputs. | Date | Mon, 10 Feb 2014 14:05:08 -0800 |
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From: David Daney <david.daney@cavium.com>
When we have a GPIO pin connected to an open-drain network, we want a standard way of specifying this in the device tree. So we choose bit 1 of the flag field to indicate open drain.
A typical use case would be something like:
enum of_gpio_flags f; . . . reset_gpio = of_get_named_gpio_flags(node, "reset", 0, &f); . . . ret = gpio_request_one(reset_gpio, (f & OF_GPIO_OPEN_DRAIN) ? GPIOF_OPEN_DRAIN : 0, "reset"); . . . gpio_direction_output(reset_gpio, 1); gpio_set_value(reset_gpio, 0); msleep(20); gpio_set_value(reset_gpio, 1); . . .
Signed-off-by: David Daney <david.daney@cavium.com> --- include/linux/of_gpio.h | 1 + 1 file changed, 1 insertion(+)
diff --git a/include/linux/of_gpio.h b/include/linux/of_gpio.h index f14123a..0e374774 100644 --- a/include/linux/of_gpio.h +++ b/include/linux/of_gpio.h @@ -30,6 +30,7 @@ struct device_node; */ enum of_gpio_flags { OF_GPIO_ACTIVE_LOW = 0x1, + OF_GPIO_OPEN_DRAIN = 0x2, }; #ifdef CONFIG_OF_GPIO -- 1.7.11.7
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