dm: gpio: Add methods for open drain setting

[oweals/u-boot.git] / include / asm-generic / gpio.h

diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h
index 2500c10450062542b0b9ba2262adb6af6a7a5c6a..4aa0004fab4b2cc67e414b395ca38f9403e950c4 100644 (file)
--- a/include/asm-generic/gpio.h
+++ b/include/asm-generic/gpio.h
@@ -251,6 +251,8 @@ struct dm_gpio_ops {
                                int value);
        int (*get_value)(struct udevice *dev, unsigned offset);
        int (*set_value)(struct udevice *dev, unsigned offset, int value);
+       int (*get_open_drain)(struct udevice *dev, unsigned offset);
+       int (*set_open_drain)(struct udevice *dev, unsigned offset, int value);
        /**
         * get_function() Get the GPIO function
         *
@@ -549,6 +551,38 @@ int dm_gpio_get_value(const struct gpio_desc *desc);
 
 int dm_gpio_set_value(const struct gpio_desc *desc, int value);
 
+/**
+ * dm_gpio_get_open_drain() - Check if open-drain-mode of a GPIO is active
+ *
+ * This checks if open-drain-mode for a GPIO is enabled or not. This method is
+ * optional.
+ *
+ * @desc:      GPIO description containing device, offset and flags,
+ *             previously returned by gpio_request_by_name()
+ * @return Value of open drain mode for GPIO (0 for inactive, 1 for active) or
+ *        -ve on error
+ */
+int dm_gpio_get_open_drain(struct gpio_desc *desc);
+
+/**
+ * dm_gpio_set_open_drain() - Switch open-drain-mode of a GPIO on or off
+ *
+ * This enables or disables open-drain mode for a GPIO. This method is
+ * optional; if the driver does not support it, nothing happens when the method
+ * is called.
+ *
+ * In open-drain mode, instead of actively driving the output (Push-pull
+ * output), the GPIO's pin is connected to the collector (for a NPN transistor)
+ * or the drain (for a MOSFET) of a transistor, respectively. The pin then
+ * either forms an open circuit or a connection to ground, depending on the
+ * state of the transistor.
+ *
+ * @desc:      GPIO description containing device, offset and flags,
+ *             previously returned by gpio_request_by_name()
+ * @return 0 if OK, -ve on error
+ */
+int dm_gpio_set_open_drain(struct gpio_desc *desc, int value);
+
 /**
  * dm_gpio_set_dir() - Set the direction for a GPIO
  *